The Extravehicular Mobility Unit AKA EMU Suit is an independent anthropomorphic spacesuit that provides environmental protection, mobility, life support, and communications for astronauts performing extra-vehicular activity (EVA) in Earth orbit. A "snoopy cap" holds microphones and headphones. A full-body liquid-cooling garment has tubes carrying cool water to remove heat from the astronaut's skin. The suits are white to reflect heat and to stand out against the blackness of space.
Not to be confused with an EVA suit or a Manned Maneuvring Unit.
Lewis inside an EMU suit.
A picture from the EMU Wikipedia page.