BIF is a settings file format used by games developed by BioWare. BIF format is used by such titles as Icewind Dale, Baldur’s Gate, or Star Wars: Knights of the Old Republic. Other developers also use this type of files in their games, for example, CD Projekt with their The Witcher game. 

BIF document file store information regarding visual and audio settings, maps, texture, etc. Game that use Infinity or Aurora game engines all use this file format. Game archived in BIF files can be unpacked using dedicated software tools.