Gobo’s uncle Matt, known as Travelling Matt, has gone into “Outer Space” (which is what the Fraggles call the normal human world) to explore, and he sends postcards back to Gobo regularly. In the North American version the connection between Fraggle Rock and Outer Space is a small hole in the wall of the workshop of an eccentric inventor called “Doc”, and Gobo must go out into Doc’s workshop to retrieve the postcards from the wastebasket where Doc throws them. Doc is unaware of the Fraggles’ existence, but his dog Sprocket has seen them and goes to great efforts to attempt to prove them to his master. Humans are known to Fraggles by the name “Silly Creatures”, bestowed by Matt after observing and interacting with them in his travels.