American Sign Language, also known as ASL or Ameslan, is the sign language predominantly used by the deaf and hard of hearing community in North America. As many as two million people in the United States use American Sign Language as their primary method of communication, making ASL the fourth most commonly used language in the country. In other parts of the world, American Sign Language is used in conjunction with French Sign Language, British Sign Language, and other regional sign languages.

One of the biggest misconceptions about American Sign Language is that it is simply English adapted for the deaf or hard of hearing. American Sign Language is its own unique language complete with specific semantics, syntax, phonology, pragmatics, and morphology. In linguistics, American Sign Language is considered to be a separate area of specialization. However, it is interesting to note that there is no grammatical tense in ASL.

American Sign Language is a unique system of communication because it is both a visual language and manual language. Instead of expressing himself through sound, a speaker using ASL employs a combination of facial expressions, body language, gestures, palm orientations, and hand shapes. Learning the subtleties of communicating in this manner can often take years of intensive study.

In American Sign Language, signs can be classified as transparent, translucent, or opaque. Signs that are transparent have meanings that are easily understood even by people who have not mastered the basics of the language. Translucent signs are understood by non-proficient speakers once the meaning has been explained. In comparison, a sign that is classified as opaque has a meaning that is not often guessed by someone who isn’t fluent in American Sign Language. Most of the signs needed to communicate clearly using American Sign Language are classified as opaque.

There are several different ways people can learn American Sign Language. Since up to 90% of all children who are born deaf have hearing parents, there are a variety of highly structured American Sign Language programs available throughout North America. Many of these programs encourage family and friends to learn the language as well in order to develop better communication with the child. American Sign Language classes are also used to fulfill foreign language study requirements at many high schools, colleges, and universities. For those looking for a less structured approach, there are numerous websites offering independent study lessons in basic American Sign Language.

American Sign Language has several other uses in addition to communication within the deaf and hard of hearing community. American Sign Language has been taught to chimpanzees, gorillas, and other non-human primates as part of various research projects. Many parents also teach their infants a modified version of American Sign Language to assist in communication before verbal skills are developed.