The main difference between MPEG4 and MPEG2 is that MPEG2 is compatible with DVDs, while MPEG4 is compatible with Blu-ray. Both media types are compatible with broadcast signals.
MPEG stands for Moving Pictures Experts Group. The MPEG2 format debuted in 1999 and was designed for broadcasting, media distribution and DVD playback. The file type consists of video and three layers of audio, with the third being MP3. MPEG4 contains video, audio (MP4) and advanced video coding. While DVDs utilize MPEG2, Blu-ray discs can utilize both MPEG2 and MPEG4. MPEG4 is also a main file format for Internet-downloaded media such as movies and music.