In general, web conferencing is made possible by Internet technologies, particularly on TCP/IP connections. Services may allow real-time point-to-point communications as well as multicast communications from one sender to many receivers. It offers data streams of text-based messages, voice and video chat to be shared simultaneously, across geographically dispersed locations. Applications for web conferencing include meetings, training events, lectures, or presentations from a web-connected computer to other web-connected computers.
Web conferencing may be used as an umbrella term for various types of online collaborative services including web seminars ("webinars"), webcasts, and peer-level web meetings. It may also be used in a more narrow sense to refer only to the peer-level web meeting context, in an attempt to disambiguate it from the other types of collaborative sessions. Terminology related to these technologies is inexact, and no generally agreed upon source or standards organization exists to provide an established usage reference.
The term "webinar" is a portmanteau of web and seminar, meaning a presentation, lecture, or workshop that is transmitted over the web. The coined term has been attacked for improper construction, since "inar" is not a valid root. Webinar was included on the Lake Superior University 2008 List of Banished Words, but was included in the Merriam-Webster dictionary that same year.
Presentation of visual materials most often is accomplished through one of two primary methodologies. The web conferencing software may show participants an image of the presenter's computer screen (or desktop). Again, depending upon the product, the software may show the entire visible desktop area or may allow selection of a physical area or application running on the presenter's computer. The second method relies on an upload and conversion process (most commonly consisting of Microsoft PowerPoint files, other Microsoft Office electronic documents, or Adobe PDF documents).