multipurpose internet mail extensions (MIME)

Standard for attaching non-text files to an internet mail message, such as animation, graphics, hypertext files, sound files, spreadsheets. MIME standard converts (encodes) non-text files into text that is normally unreadable and then, at the other end, reconverts (decodes) the files to their original form. A more secure version is called secure MIME (S/MIME).