All the file formats behind GTA V map data. See the individual pages for details. This is the index.

Map data

YMAP - object placements. The 'what's where' file. Where most of the map editing takes place.

YTYP - object type definitions. Linked from YMAPs. Specifies what the object actually is.

YBN - collision data. Stored separately from the visible geometry.

Drawables and assets

YDR - a single drawable model. This is the mesh data itself.

YDD - drawable dictionary. Several drawables bundled into one file.

YMT - metadata. Holds the properties of objects.

Other formats

YFT - stores fragment data, used for breakable objects. YPDB - stores posed data. YCD - clip dictionary used for animations. There are many smaller formats that hold data for specific subsystems.

Most mappers never interact with these lower-level formats. Common everyday formats are YMAP, YDR, YMT.