In his earliest appearances, Grover was depicted as having dark green fur and an orange nose. By the second season of Sesame Street, this was changed to the more familiar puppet with blue fur and a pink nose (although the original puppet was used for the initial appearance of Grover's mother).
Grover also has an instructional persona who wears a cap and gown to provide educational context for simple, everyday things. His lessons are often wrong, leaving himself open to correction by a group of kids or Muppets. This, combined with the failings of the Super Grover character, means that Grover is very self-conscious and timid. He is often a source of slapstick humor and often accidentally injures himself.