- Instant messaging (IM) are technologies that create the possibility of real-time text-based communication between two or more participants over the internet or some form of internal network/intranet.
- It is important to understand that what separates chat and instant messaging from technologies such as e-mail is the perceived synchronicity of the communication by the user - Chat happens in real-time.
- Some systems allow the sending of messages to people not currently logged on (offline messages), thus removing much of the difference between Instant Messaging and e-mail.
- IM allows effective and efficient communication, featuring immediate receipt of acknowledgment or reply. In certain cases Instant Messaging involves additional features, which make it even more popular, i.e. to see the other party, e.g. by using web-cams, or to talk directly for free over the Internet.
Example of instant messaging is Yahoo! Messenger, X Fire,Window Live Messenger.
- In early instant messaging programs each character appeared when it was typed. The UNIX "talk" command shown in these screenshots was popular in the 1980s and early 1990s.