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Computer Virus: Different Types of Computer Viruses and Its Effect

computer virus

Today, everybody is a computer-savvy. People who use computers, they must have heard the name of a computer virus once or twice. But what are those computer viruses? What are the effects of coming to our computer? And how many types are they? All this will not be known. So today, with the help of this article, I will try to tell you that what is a computer virus and what are its effects and how many types are there?

So, before knowing what is a computer virus, let’s see what is virus first,

What is a virus?

computer virus

The virus is a malicious full program that damages the computer’s data. This computer performs the task of erasing or deleting the data. The virus is a deliberate program written. It adds itself to the boot of the computer and the number of times the computer bits as much as the virus bits. The virus slows down its speed by reaching the hard disk’s boot. The virus associated with any program remains active as long as the program is run. When the virus remains active, it combines itself into the computer’s memory and starts spreading.

There may be several reasons for the virus to spread viruses. Infected floppy disks, or Pendrive, is helpful in spreading the virus. Viruses spread through computers, by email, games, internet, file too.

What is Computer Virus?

A computer virus is a small software program that works for the deletion of your computer system’s operation and the computer’s data loss or damage. Its main task is to slow down your computer or harm the files or data contained in it.

computer virus

Computer viruses can spoil the computer system without our knowledge in such a way that it is difficult for a person to recover. The computer runs through a lot of software programs. Computers without a program can not work Software programs are designed to make the computer work properly. While some programs are designed to spoil the computer’s work which we can call computer virus.

We all know that the computer has been invented by the person. Therefore, the computer has created its program to run the computer. The computer virus is not natural. They are not created by themselves, they also make by programmers so that they can spoil the other computer.

Effects of Computer Virus

  • Computer viruses can corrupt any of the imported data or files present on your computer.
  • It can also corrupt your system files, due to which your window may crash. And then later it has the only one solution that you may have to format your computer and may have to install a new window.
  • The virus also works to slow down your phone or computer as well as doing computer cracking.
  • The most dangerous virus effect is that it can damage your boot sector, which will cause problems in booting. And once your boot sector gets damaged, it also puts the problem in your computer formatting and it becomes very difficult to recover the computer.

Types of Computer Virus

1. Boot Sector Virus

These types of viruses are stored in the floppy and hard disk’s boot sector. When we start the computer system, this virus interferes with the loading of the operating system of the computer. But if somehow the computer starts working, then the virus starts interrupting any other computer of that computer.

2. Direct Action Virus

Direct Action Virus is a virus that never comes into your computer system alone. It just logs in to your computer system via a file (.exe and). When someone extracts or open these files, it quickly spreads to your computers. But the Direct Action Virus does not delete any files present in your computer, it can only the ability to corrupt the files.

3. Resident Virus

The resident virus is a very different type of virus. The way to do this is quite different from others. This is a very dangerous variety of viruses. It installs itself on the computer. This is even more dangerous than the direct action virus.

After installation is done, Resident Virus divides itself into two parts named Fast Infectors and Slow Infectors. The work of fast infectors is to damage the data to the computer system as quickly as possible. On in other ends, the slow infectors are very difficult to identify. It’s also hard to recognize by any antivirus.

4. Multipartite Virus

This computer virus spreads in your computer system quickly and through different directions. This works to harm your boot sector and as well as executable files. If you have cleaned or formatted your computer and if this virus is accidentally left in your computer’s boot sector, then it is generated very quickly again.

That’s why this virus is quite dangerous as the rest of the virus and spreads very quickly.

5. Polymorphic Virus

This virus is slightly less dangerous than any other virus. Detecting this virus becomes very difficult for any antivirus program. Antivirus takes about weeks or months to detect anyone polymorphic virus.

6. Overwrite Virus

This computer virus also does not cause any special damage to any files. But this can also be a very disappointing virus. It can delete any content present in your file. The only way to remove this virus is by deleting those files. It can be in any one file or it can also be present in the entire software.

7. Spacefiller Virus

Spacefiller virus is also known as Cavity Virus. It is a virus that comes with files but does not delete any kind of content on your computer or even do nothing to crack. This virus works as a filling to the entire space in your computer. It increases and spreads itself in empty spaces so that your hard disk is full and crashes.

These viruses can be dangerous to say that it can damage your hard disk. But it does not delete any kind of content, nor does any corrupt.

Also, read: What is Cyberbullying? What are its Effects and How we can Stop It?



What is Resistor? Types of Resistor and Its Characteristics

what is resistor

The resistor is the most used passive circuit element in the circuit design. And in fact, it is hard to imagine any circuit without the resistors. So, in this article, I’ll explain what is Resistor?  types of resistors, characteristics of Resistors and it’s different parameters related to resistors.

What is Resistor?

Now, as we know this resistor is the passive circuit element which opposes the flow of current and electricity. Symbolically, it can be represented by these symbols ( See on below images).

what is resistor
Image credit: All about Electronics

The property of the resistor to oppose the flow of current is known as the resistance and it is defined by the unit of Ohm. Now, for the given resistor, if 1V of voltage is applied across that resistor and if 1A current is flowing through that resistor then we can say that the resistance of that resistor is 1 Ohm.

Now, this resistor is the linear element. It means that as we increase or decrease the voltage that is applied to this resistor, the current that is flowing through this resistor will also increase or decrease. And the slope of this V-characteristic defines the resistance.

what is resistor

The relationship between the voltage, current and this resistance is defined by the Ohms Low. These resistors are available in various size an shapes.

After knowing what is resistor? Now, let’s discuss different characteristics of the resistor as aspects to

  1. Power Rating
  2. Tolerance
  3. Temperature Co-efficient
  4. Noise
  5. Frequency Response
  6. Stability

 Characteristics of Resistor

1. Power Rating

It defines the maximum power which can be handled by the resistor. Now, the power which is going to get dissipated across the resistor can be given by the simple expression of P=V×I. So, if 5 Volt of voltage is applied to the resistor and if 1A of current is flowing through that resistor then we can say that the power that is going to get dissipated across the resistor will be equal to 5W (5V×1A=5W). The power rating of that resistor should be more than the 5W.

Now, as a general rule of thumb, the resistor which we are going to use should have a power rating at least 2 to 4 times the maximum power which is going to get dissipated across that resistor. The commercially available resistors have the power rating of as low as 1/16W or as high as 300W. Apart from this power rating sometimes the manufacturers also provide the power derating curve.

what is resistor

So, this curve basically defines, with temperature how the maximum power which is going to get dissipated across the resistor will change. While selecting a particular resistor, apart from the power rating one should also need to take care of the ambient temperature of the resistor.

2. Tolerance

Tolerance defines the deviation of the resistance from the nominal value. So, let’s if you have one resistor of 100 Ohm with the tolerance of 1%, it means that the value of the resistance will be in between 101 Ohm and 99 Ohm. Now, the commercially available resistors have a tolerance value of as low as 0.1% up to 20%. And it is also even possible to achieve the lower tolerance than the 0.1%.

3. Temperature Coefficient

It defines the amount by which the resistance value changes with the temperature. This temperature constant may be either positive or negative. And generally, it is defined by the unit of ppm/C. So, let’s say we have one resistor of 100 Ohm and it is operated at 25 C. And the temperature coefficient of the resistance for that resistor is 50 ppm/C. Now, suppose if this resistor is operated at 29 c, then the value of the resistance R=100.02 Ohm. Basically, here this 50 ppm will get multiplied by the change in temperature along with the value of that resistor.

So, let’s say for some resistor if the value of this temperature coefficient of resistance is 500 ppm/C, in that case, just by a 4-degree change in the temperature, the value of the resistor will change by 0.2 Ohm. This parameter is particularly critical when the resistor is operated at high temperature. For any resistor, the value of this temperature coefficient of resistance should be as low as possible.

4. Frequency Response 

what is resistor

Generally, we assume that the resistor which we are using is purely resistive in nature. But depending upon the construction of this resistor, it also has some inductance and the capacitance. And because of that, the maximum frequency at which this resistor can be operated on will be limited.

So, while selecting a resistor for high-frequency application, one should also need to consider this parameter.

5. Noise and Stability

The stability defines how stable the resistance value will remain over the period of time. Basically, it defines the stability of the resistor. Every resistor generates its own noise. So, while selecting the resistor for low noise application, one should also need to take care of this parameter.

Now, after knowing what is Resistor and characteristics of Resistor, let’s know types of resistor

Types of Resistor

what is resistor

The resistor can be classified into two categories. The one is the fixed resistor and the second is the variable resistors. The fixed resistors mean that once the resistor is fabricated, one cannot change the value of that resistor. While in case of a variable resistor, the value of that resistor can be changed by changing the knob.

Now. let’s see the different types of fixed resistors which are used commercially.

1. Carbon Composition Resistor

what is resistor

This resistor is made up of carbon particles and the binder like a clay. These type of resistors are used in applications where you are dealing with the high energy pulses. But nowadays, these type of resistors are not used because of its poor temperature coefficient and poor stability. Apart from that these type of resistor also produces more noise and they are also less accurate.

So, Carbon Composition Resistor has been replaced by the film type of resistors.

2. Carbon Film Resistor

what is resistor

If you see the inner structure of this carbon film resistor then you may realize that on the ceramic substrate the thin layer of this carbon film has been deposited. And this film has been deposited in the form of a helix. So, just by changing the pitch of the helix, one can change the resistance value of this carbon film resistor.

Now, this type of resistors are low-cost resistors and they produce a less noise compared to the carbon composition resistor. And the tolerance value of this resistor is also less than the carbon composition resistors. So, this resistor is used in high voltage and high-temperature applications and also available in a wide range of values.

3. Metal Film Resistor

what is resistor

In the terms of construction, these resistors are very similar to the carbon film resistor. But here, instead of a carbon film, the thin layer of metal film has been deposited on a ceramic substrate. This resistor is also low-cost resistors. And in the terms of the noise and tolerance, they are better than the carbon composition resistors.

Apart from that in terms of the stability and the temperature coefficient of resistance, they’re quite good. Generally, they are preferred for the high-frequency applications.

4. Metal Oxide Film Resistor

what is resistor

In terms of the construction, they’re quite similar to the metal film and the carbon film resistors. But in this, instead of metal or carbon, the metal oxide film is deposited on the ceramic substrate. And the generally the tin oxide is used as a metal oxide layer. Now, this type of resistor is also low-cost resistor and in terms of the stability, noise and the tolerance, the performance of the metal oxide film resistor is poor than the metal film resistors.

But if you compare in terms of the carbon composition resistor, then they are much better. Also in terms of the temperature coefficient of resistance, these resistors are poor than the metal film resistors. But Metal Oxide Film Resistors are particularly used in high temperature and high surge applications.

5. Wire Wound Resistor

what is resistor

If you see the internal structure of this wire wound resistor, then the metallic resistive wire is wound around the ceramic material. So, the thickness or the gauge of the metallic wire decides the resistance of this wire wound resistor. Generally, the metal alloys like copper and the silver alloy are used for this resistive wire. This type of resistor provides the very high accuracy and also they have a very low temperature coefficient of resistance. And, because of that, they are quite suitable for high precision applications as well as for the high power applications. But wire wound resistors are not suitable for the high-frequency applications.

So, these are the different types of axial lead type of resistors which are used commercially.

Apart from that, you might have observed the tiny resistors in various PCBs and various motherboards. This tiny little resistor is known as the Surface Mount Resistors.

6. Surface Mount resistor

what is resistor

If you see the internal structure of this surface mount resistor, then you will find that on the ceramic body, the thin layer of resistive film has been deposited. Now, generally, the metal film or metal oxide film or metal oxide film is used as the resistive element for this surface mount resistor. And on top of this resistive film, the thin layer of the insulating layer has been deposited.

Now, on both sides of this surface mount resistor will find the metallic contacts. So, that this SMD resistor can be soldered on the PCB. As this Surface Mount Resistor is made up of metallic film or the metal oxide film, it is possible to achieve very high accuracy and the very low tolerance value.

Variable Resistor

what is resistor

Apart from that, the various types of variable resistor are also used in many applications. So, in this resistor just by changing the knob, it is possible to change the value of the resistor.

Also, See:  SSD vs HDD: Full Comparison of Storage Drive


So, this is all about the different types of resistors which are used commercially. We covered in this post is what is resistor? And what are characteristics of Resistor? And the types of resistors. Now, I’m sure that you understand what is resistor and its types. If you want to understand related to the resistor and it types on video series then you can click here.


SSD vs HDD: Full Comparison of Storage Drive

ssd vs hdd

In this article, we’re going to compare SSD vs HDD, which are commonly used to store the data permanently in desktop and the laptops. Now, conventionally these hard disk drives are used as a storage solution in desktop and the laptop. These hard disks drive are in use for more than two decades. But in recent years, the SSDs are gaining the popularity because of its speed and the performance.

So, in this article, let’s compare these two drives in aspects like

  1. Speed and Performance
  2. Internal Structure and Working Principal
  3. Form Factor
  4. System Interface
  5. Storage Capacity and Cost
  6. Power Consumption and Reliability
  7. Data Durability

Comparison of SSD vs HDD Storage Device

1. Speed and Performance

ssd vs hdd

The technology of hard disk drive has improved significantly over the past two decades. And the data density of this drive has increased tremendously. But the speed of the hard disk drive hasn’t increased at the same pace. Typically, the access time of today’s hard drive in the range of few ms(millisecond). And the sequential read and write speed is typically around 100 Mbps. If you are thinking the speed of the hard drive is not bad then let me tell you that the access time of the RAM and the cache memory which is used in the computer is in the range of nanoseconds. Which is significantly less than the access time of these hard drives.

So, even if you have very high-end CPU, coupled with graphics card and RAM, still you will not be able to extract the best performance out of the system if you are stuck with the slow hard disk drives. The top CPU and GPUs, the performance of the system will definitely increase. But because of the limitation of the hard drive, the system boot time and the opening of the applications will not be that fast.

While on other ends, if we talk about the SSDs, they are much faster and have access time typically in the range of microseconds. And the typical sequential read and write speed is in the range of 400 to 500 Mbps. And in fact, even if it is possible to achieve the sequential read and write speed in the range of Giga Bytes per second using this SSDs.

2. Internal Structure and Working Principal

ssd vs hdd

Now let’s look into the internal structure of these drives and their internal structure of these drives and let’s find out why SSDs are so fast and HDDs are relatively slow as compared to SSDs.

So, if you look inside the HDDs, it consists of rotating disk, which is commonly known as the platers. These platters rotate at the typical speed of 5400 or 7200 RPM in laptops and it can go up to 10,000 RPM in desktop computers. In some enterprise HDDs, the speed can go up to 15,000 RPM.

So, in these HDDs, the data is stored magnetically on these platters using the head. And typically the data is stored in this hard disk drive in form of tracks and the sectors. Now as it involves the mechanically moving parts, there is a limitation on the speed at which the data can be accessed or written on these hard disk drives.

ssd vs hdd

On the other end, the SSDs are designed using the flash memory. And to be precise if I say, they are designed using the NAND flash memory. So, as these SSDs are designed using the NAND flash memory and don’t have any moving part, they have very fast access time and very low latencies.

So, apart from the flash memory, the SSD also contains the microcontroller and the small cache memory. Using the microcontroller, the flash memory cells can be accessed or programmed. And using the cache memory it is possible to store the incoming and the outgoing data temporarily.

3. Form Factor

ssd vs hdd


Today’s HHDs are typically available in two form factors. For desktop, it is available in 3.5-inch form factors, while for a laptop it is available in 2.5-inch form factor. On the other end, the SSDs are available in many form factors. The most common is the 2.5-inch form factor, where these drives can be used or replaced in place of HDDs. Apart from these, the mSATA and the M.2 SSDs are available in very small form factors and they are used in ultrabooks and tablets.

4. System Interface

ssd vs hdd


In the comparison of SSD vs HDD, the system interface defines how these drives are connected or interfaced with the systems. So, the earlier hard drives were connected to the system using the PATA interface which is known as the parallel ATA. But today’s hard drives are connected to the system using the SATA interface. While enterprise hard drives are connected to the system using the SAS protocol. On the other end, if we talk about the SSD, mSATA, and SATA hard drives are connected to the system to the system using SATA interface. While M.2 SSD can communicate with the system using either SATA or PCI express bus.


5. Storage Capacity and Cost

Now if we compare SSD vs HDD in terms of the storage capacity then for the HDDs, 1TB capacity is most common in desktop and laptops. But for desktop, even 10 TB of the hard drives are commonly available in markets. And if we talk about the SSDs, then as of now the SSDs are available from 120 GB up to 4TB. For laptops typically, it is available from 120 GB up to 1TB. While for the desktop it is available up to 4TB.

Now, if we talk about the cost, then these SSDs are much costlier than the HDDs. As of now the cost per GB for SSD is almost 3 to 4 times the HDD cost. But as the demand for SSD is growing, the cost is also reducing. And perhaps one day, it will become as cheap as the today’s hard disk drives.

6. Power Consumption and Reliability

ssd vs hdd

HDDs involve the mechanical moving part of the power consumption of this drive is more than the SSDs. They are more prone to the damages in case of shock and the vibrations.

7. Data Durability 

ssd vs hdd

In terms of the data durability, hard drives are more durable and data can be stored for longer times without being powered up. Apart from that as we have seen SSDs are designed using the flash memory and because of that, the number of programs is erased cycles that can be performed on these SSDs are limited. Typically, it used to be in the range of 10000 to 100000. It depends upon the quality of the controller as well as the internal structure of the flash memory.

ssd vs hdd

Some manufacturers also provide the endurance rating for these SSDs and typically it is defined by the term drive writes per day. It means that the number of times the user capacity of the drive can be written per day over the warranty period. For example, if you have 100GB of a drive, which has DWPD rating of 10, it means that 1000GB or 1TB of data can be written into this drive every day over the warranty period. So, basically, this term defines the endurance rating for the SSDs. But for the most of the users, this rating is quite significant. And even if someone uses this SSD quite extensively then also it will work reliably over more than 5 years.

Also, read: What is ZIP and RAR file? How does it work?


So, overall SSDs have many advantages over the HDDs. But as of now, these SSDs are quite costlier than the hard disk drives. So if someone is looking for big storage pull, with the reasonable cost then he can go for the HDDs. While on the other end, if someone wants very fast performance and willing to pay extra money for that performance then one can go for the SSDs. Now, I hope that this SSD vs HDD comparison article has been well understood by you.



What is NFC? How NFC Works and What are its uses ?

what is nfc

Do you know what is NFC(Near Field Communication)? How does it work and what are its uses? if you don’t know what it is then read this article till the end. I’ll explain all the thing related to NFC(Near field communication).

What is NFC Technology?

Near Field Communication is a technology in which two devices are connected face-to-face wirelessly. It allows you to transfer the small amount of data between two NFC enabled devices which we’ll get to in a second and, to be honest, you actually don’t have to touch devices together. It’s near field which means you can get usually within about a centimeter of the devices and they will successfully transfer data.

NFC is the technology that makes your smartphones, tablets wearable and other devices even smarter. With just one tap you can expedite your commute and travel from checking your schedule to paying your fare. Track all your fitness and health stats. Shop save and get special offers and control everything in your home or on the road.

what is nfc

Wherever you’re headed near or far. One simple tap connects you to a world of convenience and enriched experiences from museum tours to the great outdoors to big events. You can get your tickets, buy your food and even connect with fellow fans.

How NFC Work

NFC enabled devices to communicate with each other using the radio waves. And these radio waves are generated using the antenna. So, if take the case of a smartphone, then the antenna is fitted on the battery. It is fitted on the back side of the back cover. While in case of NFC tag, if you tear down the tag then, you will find the antenna pattern. So, using those antennas, these devices are able to communicate with each other.

Now, these NFC supports the three modes of communication.

  1. Card Emulation Mode.
  2. Peer-to-Peer communication mode
  3. Reader or write mode.
1. Peer-to-Peer Communication Mode

The example of this communication mode is when we are sharing the information using the two smartphones. In this mode, both devices are active devices. And they can communicate with each other by generating the radio waves alternatively. It means that one device transmits the data at that time the second device only listens to it. And it doesn’t generate it’s own radio waves. Similarly, when the second device transmits the data, at that time the first device only listen to it. And it doesn’t generate its own radio waves. So, in this mode, both devices generate the radio wave alternatively at the carrier frequency of 13.56 MHz. And using this they can share information and files with each other.

2. Reader or Write Mode

The example of this mode is when we are accessing the data or information using the smartphone from the NFC tag. So, this mode of operation is very similar to the RFID. So, in this mode, the active device like smartphone or tablet reads or writes the data on NFC tag using the principal of Electromagnetic Induction. Now, to read the information from the NFC tag, the active device generates the radio wave at the carrier frequency of 13.56 MHz. These waves used to get coupled to the antenna of the passive tag and from this electromagnetic waves, NFC tag receives the power. So, this time-varying electromagnetic field generates the EMF or voltage in this passive tag. So, this generated voltage is rectified using the rectifier and it is used to power up the chip inside this NFC tag.

what is nfcNow, this small chip generally comprises of the clock, EEPROM, rectifier circuit and the small controller. So, once the chip is powered up then the tag responds back to the active device by the technique which is known as the load modulation. In this technique, the tag uses the internal clock of the chip and it generates the auxiliary carrier frequency of 848 KHz. Now depending upon the stored data inside this chip, the load which is connected in parallel to the antenna is turned ON and OFF. And in this way, the data is sent back to the active device. So, in this way, by the principle of electromagnetic induction, the passive tag receives the power and using the load modulation the data is sent back to the active device.

3. Card Emulation Mode

The example of this mode is when the smartphone is used for the mobile payments. So, in this mode, both devices used to be an active device. Generally, the one device used to be a smartphone and the second obviously used to be payment terminal. But in this mode, the smartphones acts like a passive smart card. They do not generate their own radio waves but they only respond back to the requested data by the payment terminal. So, in a way, the smartphone acts as a passive device. So, the operating principle of this mode is very similar to the reader or writer mode.


Also Read: Near Field Communication Technology Standard

Top 5 Use of NFC(Near Field Communication)

1. Data Transfer

what is nfc

We can transfer data between two NFC enabled phones, well NFC means near field communication which is we can say 4cm, 3cm or just attach the phone together for the transfer files. Once you do that your phone will beep and you might click the files in the phone through which you are going to transfer the file to the other phone. Well, this is one of the uses of NFC.

2. Pairing Devices

what is nfc

NFC is used for pairing devices between two NFC enabled devices. It is the fastest pairing to be known. Like in Bluetooth if pair two devices, we need to turn on the Bluetooth at first and then search the device then click the device, put the pairing pins, then later on it will start pairing…which might be a drag.

But with NFC just held the devices together at once and its done pairing, no searches, no extra pairing time or you can say you want to pair your phone to your Bluetooth speaker, which has NFC enabled. All you need to do is just held the device top of it and in seconds it will share the pairing information and done pairing.

Also whenever you want to play music, it will pair up automatically. And it will work same with other gadgets which have NFC enabled, it might be Bluetooth speakers, it might be Bluetooth headphones, anything which has NFC.

3. Mobile Wallet

what is nfc

NFC can make you look like the boss or a stupid sometimes. Well, you have heard about android pay, Samsung pay or apple pay. But do you know that these things work on NFC? I guess you all like shopping. Many of the shopping malls have cash terminals which have NFC enabled.

So, if you want to look like a Boss then you need to setup your card to your mobile wallet. All you need to do is install your mobile wallet app, whichever you use, sign up and then scan your card with your phones and then your phone will take the card information and your good to go.

So, next time when you visit the shopping mall, try to pay with your mobile wallet. Just held the phone top of the cash terminal, put the amount you want to pay, complete the transaction and look like a boss. Hopefully, the terminal should have NFC enabled.

4. NFC Tags

what is nfc

These are simple looking tags but with NFC but with NFC chips inside it, So, how do we use it? NFC tags stores a very tiny amount of data. It might be in bytes or less than in Kilobytes. Well, NFC tags can be programmed in some apps also. You can program NFC tag for setting an alarm, saving your wifi password or saving your contact details or even you can program your phone’s profile.

So, whenever your friends ask for your wifi password, just ask them to hold the phones to the tag and it will connect the wifi automatically. And if anybody asks for your contact details, you can just ask him to do the same thing. Well, each tag can perform only one task. So if you override a task upon another task in the tag it will delete the older task and take the new task.

5. NFC Business Cards

what is nfc

The NFC card enables your client to save your contact information to his NFC smartphone with simply one touch. All of your contact details including your name, title, telephone number and address would be saved. The NFC business card helps you build your network among people.

Besides, NFC allows you to link to any online contents such as a web page or a video. Now you can tailor-make what you wish people read or watch with your NFC business card. The NFC card is a chance for you to offer something truly unique and make an impact.

Apart from business cards, the NFC application can even go further. There can be NFC movie poster which allows you to buy movie tickets and watch movie trailers with simply one touch. These cards look normal but it has NFC chips inside it like the NFC tags.


So, friends, you can do a lot of work in a very short time with the help of Near Field Communication. You can also use them as home automation. Near Field Communication is a great technique with the help of which we can do many hard works in seconds. New uses for NFC technology are being developed every day. With NFC life is easier and more connected. Make sure your next smart device is NFC enabled.

So, Now, I am sure you’re familiar with what is NFC and how it works? If you find this post useful and full of information then share with your friends or any who wants to know what is NFC technology, what are its uses and how its work.


How to Lock cells in Excel Sheet (5-Easy Steps)

lock cells in excel

In this article, we learn about how you can lock cells in excel sheet. Excel is considered to be very useful. Through this, we do many things, such as storing the values, keeping the values well organized, extracting the average, making mathematics calculations, etc. straightforward and right away. Engineers use them to report their work and to store a lot of information. It is also used to store the data of banking sector customers and to update all those data regularly.

Excel is also used in many financial industries to store the data of their customers as well as to make regular updates to them. Excel is presented every new year after its new version is introduced and in some versions, some new features are added, which makes it more attractive and secure in terms of security.

Why do we need to lock cells in Excel

Suppose you have kept an excel sheet prepress and stored a lot of data and you have put too many formulas on those cells. And now you left some empty cells in that sheet to fill someone else.

But now the second person who has given your sheet to freeze the data in empty cells, it also tampering your data due to some experiments or some mistakes, or accidentally deletes it. For this reason, the entire worksheet is wasted and the time is also wasted.

lock cells in excel

In such a condition, it can be very difficult for you. So the best way to avoid this is to give permission to fill the same cells that you need to fill someone else. For this, you will need to lock all the cells you have filled up and you will need to keep the same empty cells as they are.

So that’s why we need to lock some cells to avoid this. That’s why we also have a feature in Microsoft Excel which allows us to easily lock any one of the particular cells.

Now let’s look how you can also lock cells in excel.

Steps to lock cells in Excel

 1. Go to the review section of excel sheets:

When you open the Excel sheet, there are some menu options above. Among those options, you have to select the review option.

lock cells in excel

2. Click on Allow user to edit ranges:

When you click on the Allow Users To edit ranges, it asks you how much range you want to give to the user for editing. The advantage of this is that as much as you give the range to the user, your user can edit or manipulate itself to the given range.

lock cells in excel

3. Now click on New button and give ranges

When you click on the Allow User to Edit Range, a new dialog box will open. Now you have to click on New button. After clicking, you have to name the range in the title row.

lock cells in excel


4. Select cells or cells range

After giving the name, you have to give the area or cells range where the user can edit or manipulate the data. So now you have to click on the refer to cells row icon. See on the below image.

lock cells in excel

Select the cells which you don’t want to edit or manipulate and leave those cells to which you will be allowed to edit by your user.

lock cells in excel

5. Set Password for Selected cells or cells range

Now you have to give a password for that selected range. To set a password, the bottom row in the same dialog box will contain a range password box. Now give your strong password and click on OK button. After clicking the OK button again the Confirmation Password box will be displayed. There you have to re-enter the password and click OK and again click on Apply.

lock cells in excel

Also, read: How to Block Websites in Chrome browser

Wind Up

So, in this way, you can lock cells in excel. With the help of these 5 easy steps, you can lock your selected cells in excel sheets. After locking your excel cells no one can edit or manipulate the data without your permission. This trick is very helpful for protecting your data and also save your time and work from doing reworking on that.

If you find this post helpful then share it with your work partner so that they can also protect his data and save time.

How to Transfer Photos From pc to iPhone

how to transfer photos from pc to iphone

In this article, I am sharing that how to transfer photos from pc to iPhone. You can’t exchange data like photos, videos, music or any other data with iPhone devices from any other devices. Because iPhone is a popular smartphone all over the world and due to its popularity, they also take care of the security of its devices. We can easily share data such as photos and videos in Android devices from one device to another. But if the same thing is said of iPhones, then it is very difficult to transfer all the data from one device to another.

Steps To Transfer Photos, Videos, and Music From PC to iPhone

1. Download iTunes

First of all, you need to download the software named iTune and install it in your computer system. To download, you can visit Apple’s official website or download it directly from the link provided below.

Download iTunes

2. Connect USB to iPhone with your Computer

how to transfer photos from pc to iPhone

You will have to take a USB cable and connect it to your computer system to transfer data such as photos and music. As soon as you connect your iPhone to the computer, you’ll see a mobile symbol on iTunes interface.

3. Add Data to Library

how to transfer photos from pc to iPhone

After connecting each other to the iPhone and computer, you now have to store the data that you need to transfer your phone from the computer to the computer’s library. All you need to do is copy your data that you need to transfer and paste it into a library file. if you want to add music then make music folder and add to library and if you want to add photos then simply make photos folder and add to the library.

  • Click on File
  • Now tap on Add File to Library
  • Select your photos or videos and then click on the open button.

4. Select your Data and Click on sync Button

how to transfer photos from pc to iPhone

After copying all the data, you now have to click on that little phone’s symbol. After clicking, you will move to your phone’s library. Now click on the data that you want to transfer and click on the Sync button. As soon as you click on the button, all the data that was in the library will be transferred to your iPhone.

  • Click on iPhone symbol
  • Now tap on photos
  • Select your entire data
  • Click on Sync button

Also, read: How to Lock cells in Excel Sheet (5-Easy Steps)

So, this is the way that how to transfer photos from pc to iPhone. If you want to add movies then add to library and click on sync button. This is the simplest way where you can easily send all types of file and data from pc to iPhone. If you find this post helpful then share it.

What are Zip and Rar file? How to open and create Zip and Rar files?

what is zip and rar file

If you are a regular user of the Internet and download the files in the regular time from the Internet, then you must also have downloaded such files as ZIP and RAR. But you will be among the people who do not know what are Zip and RAR files? How do I open and create this? So today I will answer all these questions through this article in all the details. So if you want to know what are Zip and Rar files and how can we open and create it, then read this article to the last.

What are Zip And Rar Files?

ZIP and RAR files are files that have .zip and .rar extensions. It can also be called a kind of archive file, which means that you have to store a lot of files inside into a single file. Keeping a lot of different files into one file is called Zip and Rar File.

Let’s understand with an example

Suppose, you want to send 10 files containing a long-sized data one by one, then you may need a lot of time and data to send it, as well as the Receiver will also need the same amount of time and data to receive or download those files. But if the same 10 pieces are collected and converted into a single file, then it will reduce your time and data cost.

Difference Between Zip File and Rar File

RAR File FormatZIP File Format
Data compression in RAR file format is goodData compression is average in ZIP file format
RAR requires an extra software called WinRAR which is available for commercial only.ZIP is generic because almost every operating systems support built in.
.rar, .rev .r00, .r01 are extension of RAR files formatextension like .zip and .zipx are called zip files format extension
1993 is initial release year of RAR files format.The Initial release of ZIP files is 1989.
Open is less in Rar file format.More Open in Zip format.

How to Open .Zip and .Rar Files on Windows

1. If you have any .rar file or any .zip file then it is very easy to open it. For open those files you will require an extra software called WinRar. I already have given the software download link to below. If you want to download through the website then you can visit on www.rarlab.com.

After installing software on your computer system just right click on your file and click on click on extract here or extract files or open with Winrar. You can choose any of the three option to open it. After choosing any of the three options your files will get extracted and saved on your desktop.

So here are simple steps of above

  • Download Winrar software and install on your computer.
  • Go to your file and click on right button.what are zip and rar files
  • Choose any of the three option extracts here, extract files, open with Winrar.

How to Create Zip and Rar Files on Computer

1. Download Winrar Software

To open or create a ZIP and RAR file, you will need to download a much-needed software called Winrar. After downloading, you will have to install this software on your computer system. This software is designed for Windows computers, which is used to create or open ZIP and RAR files.

Download 32 Bit

Download 64 Bit

2. Select Your all Files and click on Right Button

After installing Winrar software, you have to select all those files that you want to create in ZIP or RAR format. After selecting, you have to right-click your mouse and click on the Add to Archive.

Now if you want to create your files in zip format then simply select your all files >> right click on your mouse button >> click on send to >> compressed (zipped). what are zip and rar files

Note: There is no need to download any software to convert files to zip format because it is already preinstalled on Windows system. But if you want to convert all files into RAR format then you need to install WinRar software.

3. Select your Archive Format

When you click on the Add to Archive, after that a new small window will open, in which you have to give the name of the archive file and select the format of those files in ZIP or RAR.what are zip and rar files

  • Name your Archive files
  • Choose Archive Format
  • Click on Ok button

Here, you can also choose the option for creating in ZIP format of your all files. After choosing the format of your files, just click on ok button. After doing this, all your files will be converted to ZIP or RAR.

Also, Read: What is Airplane Mode? How Does Airplane mode work?


So in this way you can open or create RAR or ZIP files. Rar and zip files are very useful in sparing your time and data. I hope you have come to know now what are ZIP and RAR files? What’s the difference? How are they opened? And how are they made?

If you enjoyed this post or have proved useful, then definitely share it with your Friends and Family members.

What is Cyberbullying? What are its Effects and How we can Stop It?


What is Cyberbullying?

Cyberbullying is a form of bullying that happens online. It involves harming, harassing, threatening and humiliating a person, usually through social networks messaging apps, chat rooms as well as via email and website.

Or in other words, we can say that cyberbullying means to hurt someone in a mental form. That is, if you are troubling someone mentally or if you want to hurt him for any reason then it will be called cyberbullying. Talking to someone in a strange way that comes in front of you and if they hesitated to talk to you, we would also call it Cyberbullying.


Cyberbullying can manifest either directly online or be a continuation of bullying that has taken place in the real and physical world. At school or in the youth club for example. Wherever it starts, what is clear is that it is increasingly commonplace. Some of the most popular types of cyberbullying include spreading false rumors, posting humiliating photos or videos and creating fake profiles and website that can cause distress to the victim.

Photomontages or viral memes are also on the rise. And because they can spread quickly across the web, they can be rather difficult to stop. Anyone can be the victim. You, a member of your family, your friends too. And because of the 24/7 culture of the internet, it can happen anytime, anywhere and on any platform. Even computer games aren’t immune to these memes.

How Cyberbullying Increasing Through Whatsapp and Facebook

Nowadays Facebook and WhatsApp’s madness have increased so much that the addiction is mostly on the teenager. People spend hours on these social media platforms. That’s why cyberbullying events also arise due to these social media.


Parents give their children a mobile phone or computer, and the children use these social media to talk to an unknown person, due to which there is a possibility of the occurrence of cyberbullying incidents. Due to reasons of addiction to these social media, children are also seen busy in the streets, due to which many fatal accidents happen. Such incidents are increasing rapidly on the citizens of almost every country.

Psychological Effects of Cyberbullying

  • Low self-esteem and Confidence: This is the effects where people start thinking negatively about himself. If you have low self-esteem and low confidence level then anyone can easily troll you. If you think continues negatively about yourself then the people who want to harass you can easily track and harass you by online.
  • Vulnerability+Low self System:  Peered pressure by social groups. People laughing and sending hates.
  • Social Anxiety: This type of anxiety is where the people feel extremely shy, and self-consciousness which builds up into the powerful fear.  People with this anxiety can usually interact with their family and their close friends. But meeting new friends or speaking in public can be really hard for them, it can cause them extreme shy.cyberbullying
  • Feeling Alone: When the people feel alone then they sit on the corner of any place. Teenagers start getting bad grades on their exams and also not involving any sports and activities.
  • Anxious and Depressed: Depression is the very major on when any people get effects of cyberbullying. The result of suiciding cases gets increases. Low self-esteem and anxiety also get increased.

The worst of all effects is Suicide. There have been many stories of people suiciding because of cyberbullying. Most of the teenagers and child decide for suicide because harassing and trolling by the others person.

How to stop Cyberbullying

1. Privacy is Prevention

Take a second to go to any place you store data about yourself online and make sure that privacy settings are airtight. Google your name and see what comes up. Make sure your Facebook settings don’t give out your email address or phone number.

2. Don’t Respond and Retaliate

This is the ridiculously hard rule to follow because you’re getting sent awful things and the first thing you want to do is fire back but think of it like this though. Engaging with a bully is like pouring water on a grease fire. It seems like the obvious thing to do with the time because holy crap my stovetop is in frames but water just spreads the fire and retaliating against a cyberbully.


3. Block The Bully If Possible

What’s better than ignoring a bully. Making it possible for him to contact you that’s what try one of the following methods to make it harder for your bully to reach you. If you’re on a messaging system set it up so that only contacts on your buddy list can contact you. If this doesn’t work try going invisible or blocking the individual screen names that you know to be dangerous. Screen all incoming phone calls and text messages. If necessary temporarily suspend your social media pages.

4. Save Information and Tell Someone

First and foremost report the bullying to the service provider because cyberbullying is outlawed on most sites and messenger services. It is also illegal in most of the states. Though some bullies might think they can get away with a lot simply because nobody knows who they are. What they forget is that they’re leaving a pretty significant electronic trail. Save any threatening correspondence email, facebook, phones etc. and show it to somebody you trust.



So if you think, you are being cyberbullied, or see something that looks like cyberbullying, do not be afraid to seek help. Speak to your parents and teachers, they can offer you support and advise. Also be careful not to fall into the trap of being cyberbully yourself. You might not be aware of it, but a simple post or throwaway comment can be seen as a  form of online bullying.cyberbullying

No one likes to be bullied in the real or digital world. The best way to tackle cyberbullying is to spot the signs and report it to an adult. Be positive, and show solidarity with victims, so that everyone can enjoy safer technology.


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How to Block Websites in Chrome [Easy Method]

block website in chrome

Why do you need to block websites in Chrome browser? What is the use of this? Your children may use your computer regularly and you want to protect your child from the bad website. So that they can not open a bad website. And it can also be that you have been spending a lot of time on a website yourself and you are trying to stay away from the website, at the time of work or study. In this way, you can also check your own internet habit on your Chrome browser.

So let’s see how you can easily block any website by using your Google Chrome.

For blocking any website you will need a very popular extension which is called Site Blocker. You have to need to add it to your Google Chrome.

Steps to Add Extension on Your Google Chrome Browser

  1. Open your chrome browser
  2. Go to the 3 doted sign on the top corner of your Google Chrome
  3. click on More Tools
  4. And click on Extension
  5. Go to Get more extension
  6. Go to search bar and enter the site block
  7. Click on add to chrome and add the extension

Now that site blocker extension will be associated with your Chrome browser. You will also see an alert message “Site Blocker has been added to chrome“. When you click on that extension symbol another a small site blocker window will pop-up. Now just click on all blocked sites. When you click on all blocked sites then you will redirect to site blocker website.


block websites in chrome

Follow Below Instructions to Block Websites in Chrome

Now here you can add website which wants to block. Suppose you have to block Facebook,  then you have to insert Facebook’s URL in the box and then click on the add button. You can block multiple sites at a time. For this just insert the websites URL in the box and continue clicking the add button. All website will be added to the block list. After inserting the website you have to click on save changes.

block websites in chrome When you open these websites which you have inserted for the block, you will see a message called “This site is Block“.

block websites in chrome

Now there will be many people who don’t want to show blocked tab on their computer. Now if you want to do this then you easily do it by changing one setting. This will happen when you or any unknown person will try to open these websites then it will get closed automatically and the blocked message will not show again on any another tab on your browser. By doing this setting, nobody will know that this website has been blocked by somebody.

So to do this setting, you only need to open the site blocker’s extension. When you open that site blocker extension down towards the bottom, there will be an off/on button.

block websites in chrome

So just move that button to off to on. After doing this small changes, the blocked message will no longer available in another tab. That will get remove until you will not turn on that button.


Add Password For Extra Security

You can also place a password on this Chrome extension so that if someone else wants to delete these blocked Websites then they will not be able to do it.

Let’s see how to do it.

Go to site blocker extension and click on the set password. After clicking on set password put your favorite password in the set password box and click on save changes button. You get it done!

block websites in chrome block websites in chrome

Now if anybody wants to remove these blocked sites which you are later done, then they wouldn’t be able to do it without the password. First, they have to enter the password and then they can make changes. If they don’t know your password they can’t do it anything. So it is an additional benefit for block websites in chrome.

Note: You can also hide this extension on your chrome browser. If you want to do it then go to your chrome menu and simply just click on the site blocker extension and again press the right button on your mouse.block websites in chrome

After that, you will get a small window. On that window click on “Hide in Chrome Menu”. The extension will no longer available on your chrome menu. Doing this will not make anyone aware that you are using an extension to block sites.

Also Read: How to Hide Photo, Video, and Files Without Any App

Unblock Your blocked websites

Now if you want to remove blocked websites which you’re later get done it then you can easily do it. so let’s see how you can to do it.

block websites in chrome

First, go to the site blocker extension and you can see the cross sign on the line of URL which you’re put for blocking and click on save changes. When you click on that cross sign and make save changes the sites will get removed.


So that’s the method to block websites in chrome. This site blocker extension is awesome to use. The features of this are extremely very good. I personally used this for blocking any website.

I hope you like this post. Keep visiting this blog to find the best tips and trick.


What is Screen Overlay? And How to Fix It?

what is screen overlay

Do you know what is screen overlay and why it comes on your phone? In today’s time, almost every person uses mobile. Without a mobile phone, there is no work in today’s time. Whenever we want to find some information, we immediately search Google on the phone. Or if we are in a good place, then immediately turn the phone on the phone and take photos. The mobile phone has made life easier for the human.

Mobile is growing rapidly in the world. That’s because it has apps that help us to do our work easily. But many times when we install these apps on your mobile and give some permission while installing it, sometimes some messages are shows to us, whose name is “Screen Overlay Detected“.

Reason for having the screen overlay in mobile

The screen overlay is a very troubling problem. The reason for this is because when we give permission to an app, again and again, the screen overlay error shows. A message is also written with that is “to change this permission setting, please turn off screen overlay from setting>apps“.

A lot of people follow this step and try to make this mistake but they fail. Therefore, before solving any problem, it is very important for us to know that why this problem came from and why did it come? In the same way, before fixing the screen overlay error, it is very important to know that what is screen overlay and why and when it comes to the phone.

What is Screen overlay?

what is screen overlay
Images credit: Technology Gyan

The screen overlay is a part of the mobile app or is a feature that lets you screen the second app screen on top of an app on your mobile screen. This means that the second mobile app screening or walking on top of a mobile app is called a screen overlay.

what is screen overlay

If you do not understand yet, then let’s understand with an example.

Suppose you are talking in a message with a friend in Whatsapp and suddenly someone else’s message comes to your Facebook Messenger. So Messenger goes over the screen of a small icon on Whatsapp, which means that the overlay is done. So we can call it a screen overlay.

Now let’s follow the steps to stop screen overlay detected the error on the mobile phone.

How to Fix Screen Overlay Problem?

1. Go to the mobile settings and click on the application: 

To fix the screen overlay, first, you have to go to the settings of your phone and then click on the application’s option.

what is screen overlay  what is screen overlay

2. Click on More and then click on apps that can appear on the top.

After that, you have to click on the application manager. You will find all the apps in the application manager, which is installed on your phone. Then there will be another option above which you have to click on it is more and than click on apps that can appear.

what is screen overlay  what is screen overlay

Guy’s, If you do not see the “apps that can appear on the top”,  then you can get the option of the display over the apps.

3. Now turn off all options and close all tab.

After that here you will find many apps that are installed before you. The option that is in front of it is already turned on, so just turn off it. After that, you have to close all the tabs on your phone.

what is screen overlay   what is screen overlay

Note: All these options may be different in some people’s phones. So follow these steps to complete the process. Application ⇒ Advanced ⇒ Special app access ⇒ Display over other apps. After that, click on all the apps and turn it off or close all.

4. Now permit mobile app.

what is screen overlay   what is screen overlay

After closing all the tabs, you have to go back to the phone’s settings and click on the application. Now, you have to select the app that shows the problem of the screen overlay. After making the selection, click on Force Stop and tap permissions as you want to permit.


So after following all these steps, the problem that was being shown in your mobile apps will stop showing permissions now. Even if the message of the screen overlay is going on, then restart the phone once and follow these steps again. Doing this will make your mobile screen overlay problem solvable. So I think you understood what is screen overlay and how to fix it.


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