Tagged Image File Format
<file format, 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.