Created in 1988, it was intended for video files. A file of this format contains video and audio information, images and subtitles. When compressed, the files do not lose quality. The format includes various types of multimedia content: videos, animations, audio, 2D and 3D graphics. Files of this format can be used and viewed on the Internet. In this case, a metadata transfer takes place. The full name of the format is MPEG-4 Part 14.

ac3

AC3: a Dolby Digital audio file

This is an audio file extension that allows for achieving surround sound. It is utilized in files of the DVD format. Its manufacturing company is Dolby Digital. An AC3 file is an audio stream that can be encountered as external soundtracks for films. You can download it separately and synchronize it with the movie file. The audio file contains 6 channels: upper and lower, front and rear, right and left, as well as low-frequency effects.