Audio Audio is usually played using "RealOne Player", "MusicMatch", ITunes or "Windows Medial Player"

Real Audio (RealOne Player)

http://www.whyy.org/91FM/live40.ram
rtsp://streamer.whyy.org/encoder/live.rm

Windows Media: (Windows Medial Player)
Eg. from WHYY
http://www.whyy.org/91FM/windowsfmlive.asx
creates windowsfmlive.asf
containing:
<ASX version="3.0">
<Entry>
<ref HREF="http://WINMEDIA.whyy.org/live_radio"/>
</Entry>
</ASX>

http://www.wnyc.org/asx/wnycfm.asx
creates wnycfm.asx.asf
containing:
<ASX VERSION="3.0">
<ENTRY>
<Duration Value = "3:59:02" />
<REF HREF="mms://wnyc.wm.llnwd.net/wnyc_wnycfm" />
</ENTRY>
</ASX>

MP3 files: (MusicMatch, ITunes)

Played by a MP3 player such as MusicMatch 
 Jukebox on Windows or iTunes on a Mac.
http://www.wnyc.org/stream/wnycfm.pls

[playlist]
NumberOfEntries=1
File1=http://wnycam.streamguys.com/
Title1=WNYC AM 820
Version=2

TERMS:
VIC - VIdeo Conferencing Tool (LBNL) vat - LBNL Audio Conferencing Tool
wb - LBNL Whiteboard Tool
Meeting Maker - A suite of collaborative, time management solutions and services from MeetingMaker.com
NetMeeting - The Windows real-time collaboration and conferencing client.