ASF is a media container used by Microsoft Windows Media Player. It was designed for streaming audio and video files online. The container determines the structure of the data stream but not how the data should be encoded. Usually the files encoded by Microsoft developers have the .wma or .wmv extensions, other files have .asf extension. Such files generally have MIME type that allows sending files via the internet. The main feature of the ASF is the ability to stream playback, that is the ability to play a video or audio directly at the time of downloading data over the network.

An audio format from Apple that was developed to remove the limitations of AIFF and WAV formats. This is a container that can store sound encoded by various algorithms and track metadata. Its characteristic feature – the format doesn’t have limitations on file size and so this allows one to store infinitely long recordings.