Groucho Marx was a comedian who played the guitar and sang. His name was Julius. He was called Groucho for two reasons: 1): The grouch-bag underneath his collar, and 2): because of his character often being grouchy. He was born in 1890.
Harpo Marx played the harp and didn't talk because he forgot his lines. However, this ended up well, because he got to do the whole thing in pantomime. His name was Adolph and changed it to Arthur in 1911. He was called Harpo because he played the harp.
Chico Marx was an Italian American, and he played the piano. His name was Leonard. He was called Chico, because he was always chasing the chicks (girls).
Zeppo Marx was a singer and he wasn't funny.He left because he found the movies boring. He only appeared in 5 movies. His real first name was Herbert. He was called Zeppo because he was really interested in zeppelins.
There was a fifth Marx brother called Gummo who never acted. His real first name was Milton. He sung with Groucho.