Webcast Origins

"Webcasting" was first publicly described and presented by Brian Raila of GTE Laboratories at InterTainment '89, 1989, held in New York City, USA. Raila recognized that a viewer/listener need not download the entirety of a program to view/listen to a portion thereof, so long as the receiving device ("client computer") could, over time, receive and present data more rapidly than the user could digest the same. Raila used the term "buffered media" to describe this concept.
Raila was joined by James Paschetto of GTE Laboratories to further demonstrate the concept. Paschetto was singularly responsible for the first workable prototype of streaming media, which Raila presented and demonstrated at the Voice Mail Association of Europe 1995 Fall Meeting of October, 1995, in Montreux, Switzerland. Alan Saperstein (Visual Data, now known as Onstream Media (Nasdaq:ONSM), was the first company to feature video webcasting in June 1993 with HotelView, a travel library of two minute videos featuring thousands of hotel properties worldwide.
On November 7, 1994, WXYC, the college radio station of the University of North Carolina at Chapel Hill became the first radio station in the world to broadcast its signal over the internet.
The term webcasting was coined (in the early/mid 1990s) when webcast/streaming pioneers Mark Cuban (Audionet), Howard Gordon (Xing Technologies), William Mutual (ITV.net), Craig Schmieder (Applied Media Resources) and Peggy Miles (InterVox Communications) got together with a community of webcasters to pick a term to describe the technology of sending audio and video on the Net...that might make sense to people. The term netcasting was a consideration, but one of the early webcast community members owned a company called NetCast, so that term was not used, seeking a name that would not be branded to one company. Discussions were also conducted about the term with the National Association of Broadcasters for their books - Internet Age Broadcaster I and II, written by Peggy Miles and Dean Sakai.
The actual word "webcast" was coined by Daniel Keys Moran in his 1988 novel The Armageddon Blues:

source:Wikepedia