mp4 The MP4 file format and the .mp4 filename extension refer to the MPEG-4 part 14 digital multimedia format developed by the Moving Picture Experts Group. It is used as a multimedia container to wrap encoded digital video and audio streams, including subtitles and still images if required. In recent decades, the format has been popularized as one of the main standards for streaming media over the internet and other computer networks and for the digital distribution of large multimedia files. MP4 supports a large number of compression audio codecs allowing files in this format to maintain a relatively small size without discounting playback quality.
mp3 First released in 1995 and developed by the Fraunhofer Society, the mp3 audio format is arguably one of the most recognizable audio file format that ever existed. This digital audio encoding format hails from the lossy data compression algorithm family. The format enjoys widespread support and compatibility with most handheld music players, smartphones, computers, and in car stereos most of which have native support for the format. It is also a popular format used for distribution of audio files over computer networks such as the internet. Free mp3 encoders such as LAME and audacity give authors the tools necessary to create .mp3 files.