The MP4 file format, also known as MPEG-4 Part 14, was first introduced in 2001 by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). MP4 is a multimedia container format that can store video, audio, and other data, such as subtitles and still images. The format was designed to be flexible and adaptable to various applications, including online video sharing, mobile devices, and digital television.