rmvb The .rmvb filename extension refers to the RealMedia variable bitrate format which is an extension of the RealMedia multimedia container format. RMVB is a proprietary multimedia digital container developed and maintained by RealNetworks, an internet streaming Media Company. It is different from its closely related format .rm in that it was designed for distribution of complete multimedia content, however it does support real-time media streaming. Video and Audio streams can be encoded and packaged into this format and distributed as single files for later playback on compatible devices and software as opposed to file streaming on high bandwidth networks.
mov The .mov multimedia format is a MPEG-4 video container commonly associated with Apple's QuickTime framework. It is the movie file format most commonly praised for bringing feature length in-color movies to the Macintosh with the initial release of QuickTime in 1991. This was before anything comparable was available for the personal computer and Microsoft Windows operating system. This movie format supports multiple sequences of data or tracks categorized into audio, video, effects, and text such as subtitles. A .mov file is considered a resource file. Thus it may or may not be final i.e. it may be self-contained where all video frames and or audio samples are within the file or it may refer to external sources such as other files or data streams using movie references.