Difference between Virus,Trojan horse and Worm

03/26/2020 11 15048

DESCRIPTION:
Difference between Virus,Trojan horse and Worm

RESOLUTION:

Difference between Virus,Trojan horse and  Worm

Question:

What is a virus

A computer  virus is a computer program that can copy itself and infect a computer. A virus attaches itself to a program or file enabling it to spread from one computer to another, leaving infections as it travels

Recognized types of viruses:

1) File infector viruses: File infector viruses infect program files. These viruses normally infect executable code, such as .com and .exe files. They can infect other files when an infected program is run from floppy, hard drive, or from the network. Many of these viruses are memory resident. After memory becomes infected, any non-infected executable that runs becomes infected 

2) Boot sector viruses: Boot sector viruses infect the system area of a disk; that is, the boot record on floppy disks and hard disks.

3) Master boot record viruses: Master boot record viruses are memory-resident viruses that infect disks in the same manner as boot sector viruses. The difference between these two virus types is where the viral code is located. Master boot record infectors normally save a legitimate copy of the master boot record in a different location.

4) Multipartite viruses: Multipartite (also known as polypartite) viruses infect both boot records and program files. These are particularly difficult to repair. If the boot area is cleaned, but the files are not, the boot area will be re-infected.

What is a Trojan horse: 

Files that claim to be something desirable but, in fact, are malicious. A very important distinction between Trojan horse programs and true viruses is that they do not replicate themselves. Trojan horses contain malicious code that when triggered cause loss, or even theft, of data. For a Trojan horse to spread, you must invite these programs onto your computers; for example, by opening an email attachment or downloading and running a file from the Internet.

What is a worm:

A worm is similar to a virus by design and is considered to be a sub-class of a virus. Worms spread from computer to computer, but unlike a virus, it has the capability to travel without any human action. A worm takes advantage of file or information transport features on your system to propagate. 

What is not a virus:

Hardware problems:No viruses can physically damage computer hardware, such as chips, boards, and monitors.

The computer beeps at startup with no screen display:This is usually caused by a hardware problem during the boot process. 

Microsoft Word warns you that a document contains a macro: This does not mean that the macro is a virus.