Manual alphabet

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.

As with other forms of manual communication, Fingerspelling can be comprehended visually or tactually. The simplest visual form of fingerspelling is tracing the shape of letters in the air, or tactually, tracing letters on the hand. Fingerspelling can be one-handed such as in American Sign Language, French Sign Language and Irish Sign Language, or it can be two-handed such as in British Sign Language.

There are two families of manual alphabets used for representing the Latin alphabet in the modern world. The more common of the two is mostly produced on one hand, and can be traced back to alphabetic signs used in Europe from at least the early 15th century. The alphabet, first described completely by Spanish monks, was adopted by the Abbé de l'Épée's deaf school in Paris in the 18th century, and was then spread to deaf communities around the world in the 19th and 20th centuries via educators who had learned it in Paris. Over time, variations have emerged, brought about by natural phonetic changes that occur over time, adaptions for local written forms with special characters or diacritics (which are sometimes represented with the other hand), and avoidance of handshapes that are considered obscene in some cultures. The most widely used modern descendant is the American manual alphabet.

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