Computer Concepts in Action ©2009

Introduction:
Learn how to keep your computer from getting "sick" with a virus.

Directions:
Read the information below and apply what you learn to answer the questions.
Check your work carefully, and click Submit.

Viruses and Worms
Viruses and worms are computer programs that are intentionally designed to hurt or destroy computer systems, software, and individual files. Many thousands of these harmful programs have been released on various networks and the Internet. And more are being written every day.

• Viruses are computer programs that copy themselves into other programs stored in a computer. Viruses can be very destructive, such as erasing important files or corrupting computer memory. Some viruses are simply annoying, such as flashing a picture on your screen. Viruses are usually spread as an e-mail attachment; sometimes they are spread by sharing an infected floppy disk.
• Worms are types of viruses that copy themselves over and over again until they fill all of the storage space on a drive or network.
• A Trojan horse is a program that appears to be desirable – like a game – but once it is opened, it does something destructive. A Trojan horse could be a virus or a worm.
• Spyware and adware are two examples of 'sneaky viruses.' Spyware and adware record the Web sites you visit and the software you use, or they can force unwanted advertising onto your computer screen. Some Spyware then uses your Internet connection to send a report on how you use your computer. Spyware and adware are not specifically designed to harm your computer, but can often end up causing systems to slow down or even crash.

Prevention
Dangerous programs can enter a computer many different ways. They can be hidden in infected files on disks, via e-mail, e-mail attachments, or Internet downloads. However there are several ways to prevent viruses, worms, and other unwanted intruders.

• Anti-virus software and firewalls are powerful tools to combat viruses. Combined with an Internet connection, anti-virus software can be continually updated to help identify new viruses and prevent them from infecting your computer. Norton, MacAfee, Net Zone, and Panda are just a few of the very popular brands of anti-virus software.
• Be very careful when you download files from the Internet. Make sure you know what the file is and that it comes from a reputable source.
• Never open e-mail attachments from someone you do not know. And be very careful opening e-mail attachments from people you do know – they may not be aware that their computer sent a virus. Always scan incoming e-mail and attachments before they are opened.
• Even though a text file alone cannot be infected, text-based files (such as HTML or ASCII) can contain viruses.

Assessment Questions

1			______ are viruses that copy themselves until filling up a computer's storage space.
2			What are two types of "sneaky viruses" that are not designed to harm your computer but can still cause serious problems?
3			What are two ways a virus can infect your computer?
4			What type of software is available to help prevent viruses and worms?