rm RealNetworks, an internet streaming Media Company, is credited as the developers and owners of the proprietary RealMedia multimedia container format. The filename extension .rm refers to this format which is used as an audio and video wrapper to distribute digital media content over the internet. The first version of this container was released in 1997 and has been popularized for its ability to unpack the digital stream while it is being downloaded over computer networks such as the internet. The format is platform agnostic and works equally well on Microsoft Windows as it does on Linux or Mac OS.
mpeg Being the most broadly compatible audio and video container format from the lossy class of containers, the MPEG standards are supported by numerous audio and video products and software applications. The standards were designed to meet the growing need for digital storage of audio and video media. They both utilize a lossy compression to scale down VHS quality digital video and CD audio. The two formats, mpeg-1 and mpeg-2, are the result of the combined efforts of the moving picture experts group which was established in 1988. The mpeg-1 has its beginnings in the same year, with an initial release to public in 1993.