I honestly didn’t know that there were three different US sign languages. I knew there were different sign languages for different countries, as signing is generally something which grows organically out of the Deaf communities.
It makes sense of course. I know there are several ways of teaching ASL. (And whether or not the school focuses on the use of voice as well as signing.) But I never studied ASL in a school setting, I only picked up bits and pieces from my cousins and watching the ASL interpreters at work and concerts and such. (Though I did promise my cousin I would learn sign. Time to find classes at a local college.)
A YouTuber I was watching mentioned that she was using PSE rather than ASL and I had to go look it up. For your information:
ASL = American Sign Language, which grew out of the Deaf community and has its own grammar, etc. <– this is the language I’m familiar with
PSE = Pidgin Sign Language, which uses ASL signs with English grammar, however drops many modifiers.
SEE = Signed Exact English, which is as it says is an exact translation of English.
The article below gives a much better definition of each.