AT, graphics> (TIFF) A file formAT used for still-image bitmaps, stored in tagged fields. {ApplicATion programs} can use the tags to accept or ignore fields, depending on their capabilities. While TIFF was designed to be extensible, it lacked a core of useful functionality, so thAT most useful functions (e.g. lossless 24-bit colour) requires nonstandard, often redundant, extensions. The incompATibility of extensions has led some to expand "TIFF" as "Thousands of IncompATible File FormATs". Compare GIF, PNG, JPEG. (1997-10-11)