Web conferencing is a form of group discussion that uses text messages stored on a computer as a communication medium. It does not include various types of real-time, or synchronous, communication, such as "chat rooms", voice-based teleconferencing, or video conferencing.
A conferencing system is said to be Web-based if it uses Web browsers and servers to provide most of its functionality. Most developers of conferencing software are hurrying to adapt their products to the Web, and the result is a lot of hybrid products that use the Web to a greater or lesser extent. Hence, the boundary between Web and non-Web conferencing software is a bit blurred.