MIME type

An Internet media type, originally called a MIME type after MIME (Multipurpose Internet Mail Extensions) and sometimes a Content-type after the name of a header in several protocols whose value is such a type, is a two-part identifier for file formats on the Internet.

The identifiers were originally defined in RFC 2046 for use in e-mail sent through SMTP, but their use has expanded to other protocols such as HTTP, RTP and SIP.

A media type is composed of at least two parts: a type, a subtype, and one or more optional parameters. For example, subtypes of text type have an optional charset parameter that can be included to indicate the character encoding, and subtypes of multipart type often define a boundary between parts.

Types or subtypes that begin with x- are nonstandard (they are not registered with IANA). Subtypes that begin with vnd. are vendor-specific; subtypes in the personal or vanity tree begin with prs..

MIME is short for Multipurpose Internet Mail Extensions, a specification for formatting non-ASCII messages so that they can be sent over the Internet. Many e-mail clients now support MIME, which enables them to send and receive graphics, audio, and video files via the Internet mail system.

There are many predefined MIME types, such as GIF graphics files and PostScript files. It is also possible to define your own MIME types.

In addition to e-mail applications, Web browsers also support various MIME types. This enables the browser to display or output files that are not in HTML format.

MIME was defined in 1992 by the Internet Engineering Task Force (IETF). A new version, called S/MIME, supports encrypted messages.

List of MIME Types

For a list of MIME Types, click this link: List of MIME Types.