In it's original sense, digital means finger-related: this page
focusses upon forms of manual communication, using the hands to
express oneself.
There are two major forms of manual communication; the
single-handed varieties used primarily for communication with the
deaf, and the two-handed varieties for use with the deaf-blind.
Deaf people around the globe use the American
Sign Language manual alphabet for their needs, with the notable
exception of the sign for the letter "T" which is considered
obscene in some European countries. The alternate "T" is
shown beside the ASL version.
For the deaf-blind however, the British
Sign Language two-handed system is more widely used.