Computer viruses

Viruses are pieces of code attached to a computer program. When a computer runs an infected program, the virus launches and embeds itself in the computer’s memory. It then looks for other programs to which it can attach. This process repeats each time an infected program launches. A trigger--such as a specific date or the number of times a virus replicates itself--usually activates the virus, which then attacks the computer. Although some viruses are harmless, simply displaying annoying messages on the computer screen, others can cause irrevocable damage by erasing data.

Process

1. An individual downloads an infected program, such as a game, from the Internet.

2. When the person opens the game file, the virus loads into the computer’s memory.

3. The virus locates another program in the computer’s hard drive and attaches to it. Now two programs on the computer are corrupt.

4. The next time either program runs, the virus searches for other files to infect.

5. A trigger activates the virus, damaging the computer.

E-mail viruses

Some of the most widespread viruses, such as last year’s ILoveYou virus, have been sent via e-mail.

1. A person opens an infected e-mail attachment.

2. The virus finds the individual’s address book on the computer and sends copies of the corrupt document to everyone listed.

3. This process repeats each time an individual opens the e-mail attachment.

Prevention

* Run a secured operating system, such as UNIX or Windows NT, or buy virus protection software.

* Activate the Macro Virus Protection feature on Microsoft applications.

* Download software only from reputable sources.

* Do not open e-mail attachments that contain an executable file. Files with extensions .exe, .com and .vbs are executable. Once launched, an executable file cannot be deactivated.

Source: www.howstuffworks.com

Researched by CHRISTINE FREY/Los Angles Times