 ASL is not an adapted form of English, unlike Braille, which is a code for the English alphabet.  ASL has its own syntax (sentence structure) and grammar.  ASL is its own language, much like French, Spanish, and Italian.

 ASL is the 3 rd most common language in the United States.  ASL is only surpassed by English and Spanish with anywhere between 500,000 and 2,000,000 people in the U.S. use ASL as their primary form of communication.

 Parents can teach simple ASL signs to babies in order to help them communicate at a very young age.  Special educators often teach ASL signs to people who have difficulty communicating verbally, whether or not they can hear or not.  Primatologists (scientists who work with apes, chimpanzees, monkeys, and orangutans) teach ASL to the animals so that they can communicate with human beings.

 Sign language is not universal.  The U.S., Canada, and Mexico use American Sign Language (ASL) while England uses British Sign Language.  ASL does have some similarities to French Sign Language and the two have a few matching signs.