defltbase.inf

Setup information file Reference

An .inf file is a setup information file on Windows. The plain-text file contains sections with installation instructions. Windows Setup and the Plug and Play system read INF files to install drivers and devices. The file names the driver files, the registry entries, and the supported hardware identifiers. A driver package pairs its .inf file with a signed .cat catalog.

A file extension is only a part of the file name. It does not give a guarantee about the format or the content of a file. But on Windows, the extension selects the program that opens the file.