Acronym: Audio Video Interleave
Introduced by/when: Microsoft in November of 1992
-Introduced for part of the Video for Windows program.
-Subdivided into smaller pieces called chunks.
- Each "chunk" is identified by a FourCC tag. An .avi file takes the form of a single chunk in an RIFF formatted file, which is then subdivided into two mandatory "chunks" and one optional "chunk".
- The first sub-chunk is identified by the "hdrl" tag. This chunk is the file header and contains metadata about the video such as the width, height and the number of frames. The second sub-chunk is identified by the "movi" tag. This chunk contains the actual audio/visual data that makes up the .avi movie. The third optional sub-chunk is identified by the "idxl" tag and indexes the location of the data chunks within the file.
-Most .avi files also use the file format extensions developed by the Matrox OpenDML group in February 1996. These files are supported by Microsoft, and are known unofficially as "AVI 2.0".
-Contain both audio and video data in a standard container that allows simultaneous playback.