XLS is a proprietary binary file format called Binary Interchange File Format (BIFF) as its primary format used by Excel to store spreadsheet information. Excel 2007 uses Office Open XML as its primary file format, an XML-based container similar in design to XML-based format called XML Spreadsheet (XMLSS), first introduced in Excel 2002.
A VOB file (Video Object) is a container format contained in DVD-Video media. VOB is based on MPEG-2 program stream format, but with additional limitations and specifications in the private streams.
In computing, RAR is a proprietary file format for data compression and archiving, developed by Eugene Roshal (hence the name RAR: Roshal ARchive). The filename extension used by RAR is .rar. If a RAR-archive is broken into many smaller files (a multi-volume archive), as is often the case when it was distributed on Usenet, then those smaller files carry the extensions .rar, .r00, .r01, .r02 etc. and most unrar programs reconstruct the whole archive when provided with the .rar file.
A file with the extension .dmg (an abbreviation for disk image) uses a disk image format commonly found on Mac OS X. The format allows secure password protection as well as file compression and hence serves both security and file distribution functions.
Temporary files may be created by computer programs for a variety of purposes; principally when a program cannot allocate enough memory for its tasks, when the program is working on data bigger than architecture's address space, or as a primitive form of inter-process communication.
Flash Video is the name of a file format used to deliver video over the Internet using Adobe Flash Player (formerly known as Macromedia Flash Player) version 6, 7, 8, or 9. Until version 9 update 2 of the Flash Player, Flash Video referred to a proprietary file format, having the extension FLV. The most recent public release of Flash Player supports H.264 video and HE-AAC audio.
In computing, DOC or doc (an abbreviation of 'document') is a file extension for word processing documents; most commonly for Microsoft Word. Historically, the extension was used for documentation in plain-text format, particularly of programs or computer hardware, on a wide range of operating systems. During the 1980s, WordPerfect used DOC as the extension of their proprietary format.
