The term "webcast" derives from its original similarity to a radio or television broadcast. Early usage referred purely to transmission and consumption of streaming audio and video via the World Wide Web. Over time, webcast software vendors have added many of the same functional capabilities found in webinar software, blurring the distinction between the two terms. Webcasts are now likely to allow audience response to polls, text communication with presenters or other audience members, and other two-way communications that complement the consumption of the streamed audio/video content.
A trademark for the term WEBinar (first three letters capitalized) was registered in 1998 by Eric R. Korb (Serial Number 75478683, USPTO) and was reassigned to InterCall. The trademark registration was cancelled in 2007. Learn.com filed a claim for the term "webinar" without regard to font or style in 2006 (Serial Number 78952304, USPTO). That trademark claim was abandoned in 2007 and no subsequent filing has been made.
In February 1998, Starlight Networks released StarLive! (the exclamation point being part of the product name). The press release said "customers can access familiar Web browser interfaces to view live and pre-recorded corporate presentations, along with synchronized slides. End users can communicate directly with the presenter using real-time chat technology and other Web-based collaboration tools."
Using Webinar software participants can share audio, documents and applications with webinar attendees. This is useful when the webinar host is conducting a lecture or information session. While the presenter is speaking they can share desktop applications and documents. Today, many webinar services offer live streaming options or the ability to record your webinar and publish to YouTube and other service later.