Crew members of the space shuttle are required to wear their space suits for launch and landing. Soviet cosmonauts are required to wear them during takeoff, landing,and docking a big difference from when they originally used to fly in only their underwear.
Space suits come in different sizes, and the various body parts, such as the arms and legs, attach together for a customized fit. The inner suit is made of a layer of tubing, which is filled with a cool liquid; the outer suit is made of multiple layers of materials such as Dacron, nylon, and aluminum (Mylar). The boots come attached to the pants, and the middle part of the spacesuit, which covers the torso, is made of inflexible fiberglass. In all, the modern space suit is like a modern-day suit of arms, which is put over the head. Built-in backpacks hold life-support systems, a camera, and other useful items for space exploration.