chat

The word chat is typically associated with "Real-time" online conferencing [L1 ]. Tcl has been the basis for MANY implementations of chatting software, including

• Alvaro's Messenger - a client for MSN Messenger
• TAC and TiK
• TkChat is the gateway to our very own Tcl chatroom - one of the best places on earth to get quick Tcl advice, or discuss with members of the TCT.
• Tkabber
• Coccinella
• RelayChat
• [numerous others]

FPX: As for the difference between chat and IM -- I'd say that a chat is something that two or more people sign up (log in) for (like IRC), whereas an IM is spontaneous. According to that definition, only the first IM message would be instant; after that (when the recipient accepts the conversation), IM becomes a chat.

see also instant messaging.