File Extension TDR File Format Contents of Arvid Tape TDR stands for Contents of Arvid Tape. 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 ANSI approves new Auxiliary Memory tape standard Forget Digital Storage -- Let's Bring Back the Cassette How should we backup 20 TB of data?