Textual interaction (synchronous) is one of the Synchronous Computer Mediated Communications (SCMC). Computer Mediated Communication (CMC) is defined as any communicative transaction which occurs through the use of two or more networked computers. In synchronous communications all participants are online at the same time. Audio-visual and graphical interaction can also be forms of synchronous communication.

The term ‘textual interaction (synchronous)’ refers to a two-way, real-time textual communication, for example using Internet chat software. Online chat can refer to any kind of communication over the Internet, but it is primarily meant to refer to direct one-to-one chat or text-based group chat (formerly also known as synchronous conferencing), using tools such as instant messengers; Internet Relay Chat; talkers, and possibly Multi-User Dungeon (MUD), a multi-user, real-time virtual world described entirely in text.

Related methods include: Audio-Visual Interaction (Synchronous), Graphical Interaction (Synchronous) and Virtual world modelling.