IWD is an extension characteristic of files associated with some parts of the popular series of video games called Call of Duty. IWD are files used to store internal game data. The data in these files is compressed, which allows you to use less space on the storage medium. Technically, these are ZIP archives. These files contain graphic and audio data. IWD files are not intended to be directly opened or modified by the user.

Call of Duty is a series of FPS war games published by Activision.