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.
Is a new media container format from Google. Based on video codecs line VP8(9). Its main task is a replacing the old standard MPEG-4. The format is supported by all browsers and is integrated in Adobe Flash technology. For audio codec Vorbis is used; for subtitles and metadata is a the Matroska container.