MPEG-2 (aka H.222/H.262 as defined by the ITU) is a standard for the generic coding of moving pictures and ISO/IEC 13818 MPEG-2 at the ISO Store. It describes a combination of lossy video compression and lossy audio data compression methods, which permit storage and transmission of movies using currently available storage media and transmission bandwidth.
Is a video format similar to MP4. The difference between the formats is their developers and protection. Apple company, has developed a format that has provided DRM-lock for M4V. Video files in this format are downloaded from iTunes.