Synchronous communication via the Internet. Typically, online chat allows a group of users to see the participants contribution as it is typed allowing for dialogue that approximates a face-to-face conversation. Increasingly online chat is being replaced by technologies that allow telephone-like voice conferencing over a network or the Internet.

a virtual meeting point for researchers and users where discussions are held about topics like literature, history, education, philosophy, literary creation, etc

Chat allows the Instructor and Students to participate in real-time, online classroom discussions and presentations. Synchronous communication.

Real-time communication between two users via computer. Once a chat has been initiated, either user can enter text by typing on the keyboard and the entered text will appear on the other user's monitor.

Online chat can refer to any kind of communication over the internet, but is primarily meant to refer to direct 1-on-1 chat or text-based group chat (formally also known as synchronous conferencing), using tools such as instant messaging applications—computer programs, Internet Relay Chat, talkers and possibly MUDs, MUCKs, MUSHes and MOOes.