Its our job to know where they hide and how
to remove all infected files. Not only your information can be stolen
but also your computer can be compromised (used to spread the infected
files) and slow your computer to a crawl.
About Malware includes Viruses, Worms, Trojans and
Short for "malicious software," malware refers to software programs
designed to damage or do other unwanted actions on a computer system.
In Spanish, "mal" is a prefix that means "bad," making the term "badware,"
which is a good way to remember it (even if you're not Spanish). Common
examples of malware include viruses, worms, trojan horses, and spyware.
Viruses, for example, can cause havoc on a computer's hard drive by
deleting files or directory information. Spyware can gather data from
a user's system without the user knowing it. This can include anything
from the Web pages a user visits to personal information, such as
credit card numbers.
There are two major categories of viruses:
Boot Sector Viruses
Boot sector viruses infect the boot sector of a disk, therefore affecting the computer system during the start-up process.
The boot sector is a small area on a disk which is read by the computer when it is turned on (booted).
The most common way for a system to become infected is when an infected disk is left in the disk drive
when the computer is being booted. The computer will read the virus from the boot sector and infect
the entire system. These viruses are difficult to deal with because they are read during the start-up
process even before the system is able to load its antivirus software to detect the virus.
File Infector Viruses
File infector viruses affect the program files that a system must load in order to make software function.
The virus infects a file (usually files ending in ".COM" or ".EXE") by overwriting part of the program.
By overwriting the program the virus replaces part of the program code with viral code. When the program
is executed, the virus code is executed and it infects more files.
Here are some other types of viruses:
Memory Resident Viruses
These viruses hide in memory and are difficult to detect. When the virus is in memory it will
infect any uninfected file that is executed. The only way to remove the virus is to turn the
power of the infected computer off.
Non-memory Resident Viruses
These viruses infect files and are executed each time the infected file is executed. However, they do not reside in memory.
Multi-partite viruses have characteristics of the boot strap virus and the file infector virus. They can infect .COM and
.EXE files as well as the boot sector of diskettes and hard drives.
Stealth viruses hide the changes that they've made in files or boot records so that antiviral programs can't detect them through these changes.
Polymorphic viruses scramble their code each time they replicate so that none of its copies are the same.
This makes it difficult for virus scanners to detect it because scanners search for a particular code.
Here is some research for viruses, trojans and worms.
Feel free to click on viruses from to get a full description.