File with an .IFO extension contains information regarding contents of a movie DVD, that comprises of a headline that defines a type of information and location of a given piece of content, for instance – a start window, beginnings of specific chapters, sound tracks placing. It enables navigating through the content and playing a given DVD video.

Main information file of a movie DVD that enables playing its content is a VIDEO_TS_.IFO file. IFO files are utilised by DVD players. They do not contain the content itself but the information about it. Along with VOB and VRO and BUP files, they constitute a complete DVD disc.