M4V is a digital video file format that is similar to the MP4 format, but is primarily used by Apple devices and services. The format is used for storing and sharing video content on Apple's iTunes Store, as well as on other Apple devices such as iPhones, iPads, and iPods. M4V files use the H.264 video codec and the AAC audio codec to compress video and audio data, respectively. This allows for high-quality video playback with relatively small file sizes. The format also supports digital rights management (DRM) technology, which allows content providers to restrict access to their content and prevent unauthorized copying. M4V files can be played back on a variety of media players, including Apple's iTunes and QuickTime players, as well as on other media players that support the H.264 and AAC codecs. The format can also be converted to other more widely supported video formats like MP4 using compatible media conversion software. Overall, M4V is a useful video file format for sharing and distributing video content on Apple devices and services, particularly for content providers who want to protect their content using DRM technology.