Instant messaging (often abbreviated as IM) is a text-based instant form of communication between users connected to a network, usually the Internet. It is one of the newest and most widespread forms of telecommunications technology. In fact, chances are that if you are reading this, you are probably familiar with at least one or two instant messaging services and use them with some frequency.

Instant messaging, like the Internet itself, has revolutionized the way we communicate, and perhaps even the way we perceive each other. It has allowed news and ideas to travel between people, well, instantly, and without the hassles of snail mail, or even the costs of a telephone service. Since it is text-based (although the newest forms of IM software have incorporated the ability to share other data–audio, video, etc.), it allows for a greater degree of privacy and anonymity than more traditional forms of communication.

The first forms of instant messaging were developed in a completely text-based environment, and the text typed by one interlocutor appeared to the other in “real time,” as it was being typed. However, the invention of GUI (graphical user interfaces) for operating systems such as UNIX and Windows has allowed the development of instant messaging software that was user-friendly, easy to use by the layperson, and visually pleasing to the user.

The ease and informal nature of communication through instant messaging has led to certain linguistic developments, various IM and text message terminology that made instant messaging even faster and more convenient, and has contributed new additions and abbreviations to the English language (some notable examples include “LOL” for “laughing out loud,” “TTYL” for “talk to you later,” “BRB” for “be right back,” among others).

Some of the most widespread IM software out there include AIM (which stands for AOL Instant Messenger), Yahoo Messenger, and ICQ (owned by America Online since 1998).