A WMV file is a video file based on the Microsoft Advanced Systems Format (ASF) container format and compressed with Windows Media compression. It contains video encoded with one of Microsoft's Windows Media Video (WMV) proprietary codecs and is similar to an .ASF file.
WMV file open in Microsoft Windows Media Player
The WMV file is one of the most common files used to store video in Windows. You may see the file when downloading video from the Internet or when someone shares a video via USB device or email. You can watch video stored in WMV files with a variety of media players. Windows Video and Media Player are popular choices since they come installed with many Windows operating systems.
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 WMV files.
NOTE: Windows Media Audio (WMA) files are saved with a .WMA extension.