Many programs and desktops use the MIME system to represent the types of files. Frequently, it is necessary to work out the correct MIME type for a file. This is generally done by examining the file's name or contents, and looking up the correct MIME type in a database. For interoperability, it is useful for different programs to use the same database so that different programs agree on the type of a file, and new rules for determining the type apply to all programs. This package contains the core database of common types and the update-mime-database command used to extend it.