As of Jan. 2006, the Windows Media platform includes eight codecs. Most of these codecs were introduced as part of the Windows Media 9 Series-a fall 2001 upgrade to the entire Windows Media platform-and are supported by all Windows Media 9 or later products.

Despite their names, however, two of these codecs were released after the 9 Series: WMV 9 Professional and WMV 9 Image Version 2. Thus, even though they are “9” codecs, they may not be fully compatible with the “9” versions of other Windows Media tools. For example, to encode files in WMV 9 Professional, users need both the Windows Media Encoder 9 and Windows Media Player 10-the Player installs the new codec, which then appears as an encoding option in the Encoder.

Codec	Description	Main or Intended Uses
Windows Media Audio (WMA) 9	Standard audio codec	Downloading or streaming music over an IP network (including the Internet); transferring music to portable devices
WMA 9 Professional	High-definition

As of Dec. 2004, the Windows Media platform includes nine codecs. Most of these codecs were introduced as part of the Windows Media 9 Series-a fall 2001 upgrade to the entire Windows Media platform-and are supported by all Windows Media 9 or later products.

Despite their names, however, two of these codecs were released after the 9 Series: WMV 9 Professional and WMV 9 Image Version 2. Thus, even though they are “9” codecs, they may not be fully compatible with the “9” versions of other Windows Media tools. For example, to encode files in WMV 9 Professional, users need both the Windows Media Encoder 9 and Windows Media Player 10-the Player installs the new codec, which then appears as an encoding option in the Encoder.

Codec	Description	Main or Intended Uses
Windows Media Audio (WMA) 9	Standard audio codec	Downloading or streaming music over an IP network (including the Internet); transferring music to portable devices
WMA 9 Professional	High-definition