3. BRAILLE
It is a system of thought tactile
reading and writing for the blind.
Letters are represented according to
the placement of the points
It’s an alphabet
5. MORSE CODE
It is a system of representing letters and
numbers using signals intermittently
It was developed by Alfred Vail in 1830
Morse code was used in telegraph lines
7. SIGN LANGUAGE
Deaf people can establish a channel of
communication with people
Was also used to communicate with
other people and other lenguages
It has been subject to a linguistic change