A WMA file is an audio file saved in the Advanced Systems Format (ASF) proprietary format developed by Microsoft. It contains Windows Media Audio and metadata objects such as the title, artist, album, and genre of the track. WMA files are similar to .MP3 files and primarily used for streaming music from the web.

WMA file open in Microsoft Windows Media Player 12 ASF is Microsoft's proprietary digital audio and video container format. If it contains Windows Media Video instead of Windows Media Audio it uses the .WMV extension. WMA and WMV files are the same as .ASF files but are more commonly used. Microsoft Windows Media Player 9 was the last version of the Windows Media Player developed for Mac OS X. However, Mac users can use Flip4Mac WMV (also known as Microsoft Windows Media Components for QuickTime) to play WMA files.