There are several different kinds of Chat. All are meant to serve as a way to instantly type, talk, text with others using the same chat program or service.

Instant Message Clients (IM Programs)
A Instant Message Program refers to software that is installed on your computer allowing you to chat with others using the same program. Communication is from program to program.

IRC - Internet Relay Chat
IRC (Internet Relay Chat) takes place on the Internet through IRC Servers. You download a software "application" and chat through an IRC server (a computer that hosts chatrooms) There are several chat rooms on each IRC Server.

Singles and Matchmaking
Match is the leading online dating resource for singles. Meet, flirt, date and fall in love. Find Singles Near You for FREE

Online Meetings, Conferences, Webinars - Chat / Communicate, Large Groups and Presentations
Online Meetings and Web Events Made Easy. Easy to use Web conferencing services enable you to conduct online meetings anytime, anywhere.

Unlimited online meetings with up to 25 attendees, all for one low flat rate.

Unlimited Webinars with up to 1,000 attendees for one affordable flat rate, plus a free GoToMeeting license