What is instant messaging?

Warning: To avoid viruses spread via instant messaging (IM), think before you click; if you receive a message out of the blue, with nothing more than a link and/or general text, do not click it. For more information, see If I use instant messaging software, how can I keep my computer secure?

Instant messaging (IM; also called "instant messenger") is a "presence" technology, meaning that your device (e.g., handheld or desktop computer) is identified when you connect to the network. IM applications function in real time, similar to a telephone conversation; they allow people to make immediate exchanges, and more simply than email. Some examples of IM applications are AIM, IRC, and ICQ.

IM applications require accounts or downloaded software, and for the participants to be online at the same time.

IM accounts can fall prey to security exploits, using social engineering to lead victims to worms and other malicious code. When using IM technology, be aware of who you're chatting with and don't click links unless you are sure of their source and sender.

Also see:

• What are Osama Capture, BuddyLinks, Run Saddam Run, and PSD Tools, and how can I remove them?
• What should I do if my computer is infected with an instant messaging (IM) Trojan?
• If I use instant messaging software, how can I keep my computer secure?