mimetypes

A MIME type or "media type" is a text string that identifies a particular file format.

It consists of two parts - a type and a subtype - separated by a slash.

For example, the MIME type of a plain text file is:

text/plain

Mimetypes and their interaction can be edited with the xdg tool.

The mimetype-list includes a large list of mimetypes and their matching file extensions.