DIR, Adobe Director Movie (.dir)
The DIR Video file format
DIR files are, while belonging in the video file category, no proper video files. They are rather project files created by the Macromedia Director program, a movie editing and animation program that was later acquired by Adobe. Unlike "proper" video files like AVI or MP4, DIR files can not be played using any video playing software. DIR files can only be accessed and opened in Adobe Director.
Technical details of DIR files
Since DIR files are project files of a movie or animation created and edited in Adobe Director, they do not contain actual video data. Instead, the files contain information about all the project's resources. This includes links to the resources used (images, music, videos), code and a timeline that states in which order the single files are arranged to form the movie.