downloaded so that the playback can begin while the remainder of the file is still down-
loading. This allows the user to see and hear the file without waiting for the complete file
to be received. The alternatives to streaming data are files in a nonstreaming format, such
as WAV or MPEG files. Nonstreaming files must be downloaded entirely before they can
begin playing. Your browser could include support for streaming files, but most likely
will require a plug-in player for each separate format on the Web.
Media Player
Microsoft has recently combined its streaming data formats (Advanced Streaming For-
mat (ASF) and Advanced Authoring Format (AAF), and NetShow) into the Windows
Media Player architecture. The file formats of this architecture are recognized by their file
extensions, ASF and WMA.
RealNetworks
RealNetworks combined two pre-existing technologies (RealAudio and RealVideo) to
create a streaming media architecture that is focused exclusively on delivering media on
the Internet. The RealPlayer, shown in Figure 21-9, supports both live interactive and
on-demand video and audio.
Chapter 21: Audio/Visual Devices^559
Figure 21-9. The RealPlayer streaming media client