is sign language the same in every language?
No one form of sign language is universal.
Different sign languages are used in different countries or regions. For example, British Sign Language (BSL) is a different language from ASL, and Americans who know ASL may not understand BSL.
A sign language (also signed language) is a language which chiefly uses manual communication to convey meaning, as opposed to acoustically conveyed sound patterns. This can involve simultaneously combining hand shapes, orientation and movement of the hands, arms or body, and facial expressions to express a speaker’s thoughts.
Sign languages share many similarities with spoken languages (sometimes called “oral languages”, which depend primarily on sound), which is why linguists consider both to be natural languages.
Although there are also some significant differences between signed and spoken languages, such as how they use space grammatically, sign languages show the same linguistic properties and use the same language faculty as do spoken languages. They should not be confused with body language, which is a kind of non-linguistic communication.