In 1996, PlaceWare was founded as a spinoff from Xerox PARC. In November of that year, PlaceWare Auditorium was described in a public talk at Stanford University as allowing "one or more people to give an interactive, online, multimedia presentation via the Web to hundreds or thousands of simultaneous attendees; the presentation can include slides (made in PowerPoint or any GIF-image editor), live annotation on the slide images, real-time polls of the audience, live audio from the presenter and those asking questions, private text and audio conversations in the auditorium's "rows", and other features." PlaceWare Auditorium was formally announced in March 1997 at a price of $150 per simultaneous user.
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.