Fingerspelling (or
dactylology) is the representation of the
letters of a
writing system, and sometimes
numeral systems, using only the hands. These
manual alphabets (also known as
finger alphabets or
hand alphabets), have often been used in
deaf education, and have subsequently been adopted as a distinct part of a number of
sign languages; there are about forty manual alphabets around the world. Historically, manual alphabets have had a number of additional applications—including use as
ciphers, as
mnemonics, and in silent religious settings.