File Extension MIME File Format See MIM. MIME stands for See MIM.. This was last updated in March 2012 By Margaret Rouse Browse File Extensions Alphabetically: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # Ask a Question. Find an Answer. Ask your peers a question about this file extension. Ask a Question Mobile App Management standards will just get in the way of progress Outlook web security S/MIME and PGP: How do they differ?