MP4 is a file extension abbreviated of MPEG-4 Part 14. It is a media container format, that is, it is not in itself a coding format, but contains inside itself files of other formats.
MP4 is used to combine video and audio files, images, as well as subtitles and metadata (information about the file and its contents, such as date of creation, album names, etc.). In addition to using on individual devices, the MP4 format support broadcasting over the Internet, and therefore has gained particular popularity among various online video players.
Often, users need to get an audio track from video packed in MP4 format, which makes it necessary to convert MP4 to MP3. Technically, this process is divided into two stages: extracting audio content from the container and transferring it into MP3 format.