Internet Relay Chat (IRC) networks accommodate digital chatting in the form of ASCII-based character messaging. mIRC offers closed discussion forums known as 'channels’ or private messaging between individual pairs of users.

IRC, which is an open protocol using IP/TCP protocols, has been around since the 1980s where it was used for fairly primitive BBS and local networking systems. These tools grew as the Internet grew, and the modern mIRC interface shows how simpler command line based interfaces have been replaced by a Windows-based and icon-driven menu system.

Other features of modern mIRC include buddy lists, file transfer capability, multi-server connections, compatibility with IPv6, SSL encryption and even sound and audio components. mIRC also has its own scripting for display features and more.

In using mIRC and other IRC systems, users have come up with a wide variety of terminology called 'chat slang’ where combinations of characters are used to create visuals or abbreviations are used to communicate ideas and emotions. A lot of this chat slang has also become useful in e-mail and other digital text-based communication.