Database of file type definitions used by TrID, a software utility that can identify file types based on their binary signatures; saved as a separate file and can be updated by downloading new versions of the definitions library.

The main definitions package is named "TrIDDefs.TRD" and is loaded when the application is opened. Files selected by the user are checked against the definitions in the TrIDDefs.TRD file to determine the file type.

TrID is a free program developed by Marco Pontello. The program and file definition updates can be downloaded from the TrID home page.