did mj invent the moonwalk? and can anybody do it as graceful as he does it

Moonwalking was not invented by Michael Jackson (and he has never claimed that it was). He did coin the term however. Prior to him, it was called a 'backslide', or 'popping'. The earliest film record of someone doing the 'moonwalk' is Cab Calloway in the 1932 Talkartoon film 'Minnie the Moocher'. Michael Jackson was taught this dance move by Solid Gold dancer 'Cooley' Jackson, and was first performed by MJ on the Motown 25 television special in 1983.

He got the moonwalk effect from this guy they called Turbo, he's a strutter from the movie Breakdance: There's no stopping us! You should see him dance and strut! He's too cool.