WEM file extension was developed by Audiokinetic for their Wwise audio engine (WaveWorks Interactive Sound Engine). WEM file contains audio data encoded in proprietary Wwise format. WEM files are commonly used in video game development.

This format allows sound to be modified in real-time during gameplay. WEM files are supported by audio engines that offer interactive audio solutions. WEM files are usually packaged along with game files and seldom used as stand-alone files.