A small blip printed on or notched into various storage media used for timing or counting purposes.
To identify a block of text in order to perform some task on it such as deletion, copying and moving.
To identify an item for future reference.
In digital electronics, a 1 bit. Contrast with space
On magnetic disk, a recorded character used to identify the beginning of a track.
In optical recognition and mark sensing, a pencil line in a preprinted box.
On magnetic tape, a tape mark
is a special character that is recorded after the last character of data.