Graphics Interchange Format

Graphics Interchange Format (.gif) is a standard for digitized images compressed with the algorithm, defined in 1987 by CompuServe (CIS). Though its usage for raster graphics with transparencies has largely been superseded by Portable Network Graphics (.png) as a -free alternative, GIF remains a popular format for simple web animations.

Description
Graphics Interchange Format and GIF were service marks of CompuServe Incorporated. This only affects use of GIF within CompuServe, and pass-through licensing for software to access them, it doesn't affect anyone else's use of GIF. It followed from a 1994 legal action by against CIS for violating Unisys's  software. The CompuServe's vice president has stated that "CompuServe is committed to keeping the GIF 89A specification as an open, fully-supported, non-proprietary specification for the entire on-line community including the web".