Sign language is a manual communication that is commonly used by those people who are deaf or impaired hearing problems. Sign language is not universal and deaf people from several countries speak different sign languages. It means that each country has different sign languages for deaf people to talk to their families and friends. The symbols or gestures in sign language are organized in linguistically and each individual gesture is known as a sign. In sign language, each sign has three different parts such as the movement of the hands, the handshape, and the position of the hands.

Sign language also means communication through bodily movements especially the use of arms and hands are used to communicate with another person. This type of language may be coarsely expressed as shrugs or pointing or it can employ a delicately nuanced combination of coded manual signals reinforced through facial expression and perhaps augmented by using words spelled out in a manual alphabet. Vocal communication is impossible between speakers of mutually incomprehensible languages or when one or more would be people are deaf, sign language may help in bridging the gap.

Indian sign language was organized through the use of an explicit vocabulary of gestures depicting or representing actions, objects, and ideas but it did not attempt to spell out or else represent words which could not convey through gestures. There are different forms of sign language were developed for enabling signers to spell out sounds and words. Most of these are flexible and complex as spoken languages.