This is version 0.4 of the Shared MIME-info Database spec, last updated 20 April 2002.

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 specification attempts to unify the type-guessing systems currently in use by GNOME, KDE and ROX. Only the name-to-type and contents-to-type mappings are covered by this spec; other MIME type information, such as the default handler for a particular type, or the icon to use to display it in a file manager, are not covered since these are a matter of style.

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.