Threats to Computers

What are computer viruses?

Any computer software designed to spread from one computer to another and to interfere negatively with the computer operations is called a virus. Viruses are embedded in legitimate software programs to be transmitted, when the program is copied, from one computer to another. Threats to computer security, in the form of a viruses, take different forms. Worms, for example, are viruses that replicate themselves from one computer to another, through the Internet or any other network connection.

What are the signs that a computer is infected by a virus?

Some of the signs, but not all, are

• Computer starting and running very slowly
  
• Computer stops working (freezes)
  
• Computer crashes
  
• Applications starting by themselves

How are computer viruses transmitted?

A computer virus may be transmitted

• through the internet: browsing infected web pages, downloading of infected files, ...
• by means of removable media such as CD's, flash drives, external hard drives,...
• through emails and their attachments

How to protect your computer from viruses?

• Use a reliable antivirus software to protect your computer
• Do not click on untrusted links.
• Do not click on attachments unless you know the source. Attachments have often been used to transmit viruses.
• Make sure your firewall is turned and do not accept access to your computer from the Internet
• Do not download files that you do not trust