Virus is the worst of malwares (rogue programs) that causes serious havoc to your computer system. A virus is self-replicating and affects computer hardware, software, and even the Operating System. Viruses are designed to replicate themselves and to elude detection from anti-virus software, so without a good antivirus software it might be impossible to dig them out of your computer system.
Computer virus is an executable program written with the intention of causing a wreck to your computer or network, and because viruses are programs, they are loaded into computer memory, executed and instruct the computer to perform the actions dictated by the virus.
A virus can instruct infected computer to re-write the virus onto other computers in the network thereby spreading the virus from one computer to the next. A virus payload may also delete files from hard drive, write itself to another program, or even spread across the internet through file attachments.
Virus may fall into one of these categories;
1) Parasitic - infects executable files or programs in the computer
2) Bootstrap sector - infect the boot sector of the hard disk where OS start-up files are stored on the first partition.
3) Data file - These types of viruses can open, manipulate and close data files, and are usually written in macro language. They mostly affect Microsoft Office Word document
4) Companion - this type of virus creates a program with same name as another program that already exist on the computer, tricking the computer to run the rogue program instead of the real program.
Protect yourself by backing up your computer regularly so that in case there is an infection you can restore your system from the back up. It is also important you have very reliable anti-virus software on your machine. Good anti-virus must self-updates its database from time to time so that it can prevent you from a new attack.
Stop wasting time and money, click here for best computer security softwares and tools. Testing and review have been done for you.