Assembly is a type of low-level programming language. As far as why the first 5 letters are capitalized, I'm not sure.
I was thinking in terms of assemble as in to put something together which could have been refurring to all the content that is still in a unfinished state EDIT: ASSEM being to put together and bler being the person doing it but that's just my guess
Precisely, though many people refer to the mnemonic "language" as "assembler" and the assembler as "compiler", which typically implies some sort of code generation. People are learning though, it was much worse 10 years ago.