MPEG-4 is a standard used primarily to compress audio and video (AV) digital data.
Introduced in late 1998, it is the designation for a group of audio and video coding standards and
related technology agreed upon by the ISO/IEC Moving Picture Experts Group (MPEG). The uses for the
MPEG-4 standard are web (streaming media) and CD distribution, conversation (videophone), and broadcast
television, all of which benefit from compressing the AV stream. MPEG-4 absorbs many of the features
of MPEG-1 and MPEG-2 and other related standards, adding new features such as (extended) VRML support
for 3D rendering, object-oriented composite files (including audio, video and VRML objects), support
for externally-specified Digital Rights Management and various types of interactivity.
AAC (Advanced Audio Codec) was standardized as an adjunct to MPEG-2 (as Part 7) before MPEG-4 was issued.