The cockpit is where the pilot, copilot and navigator sit. It is the control center of the airplane. Side-by-side seats, similar to car seats, face the front windshield. The pilot and copilot both sit in the seats, and have controls, such as a steering wheel, at arms reach from them. The controls allows them to fly the airplane. A third seat is at a desk. This is the navigator's station. The navigator plots the course of the airplane and keeps an eye on things such as weather reports and fuel usage. The cockpit is made as small as possible, while still remaining comfortable. This is because as much room as possible must be allowed for cargo.
After the cockpit is the cargo area. This is a huge, wide-open area. For example, the B757 airplane used by United Parcel Service has 1,790 cubic feet of cargo area. To put this into perspective, a school bus can almost fit inside the cargo area. Cargo is hauled in by truck or by a specialized truck called a lift truck or high-low truck. Any type of cargo can be carried, from animals to machinery to household goods.
Strapping is an essential part of the cargo area. If no straps were used, the cargo could shift and bounce around. Special straps are made out of very strong material to keep the cargo in place. Straps are secured to the insides of the airplane by special hooks. These hooks are strong enough so they don't break when the strap is being pulled on by the cargo.
The pilot, copilot and navigator are all human and so a bathroom is provided. The bathroom is also made as small as possible, again because most of the interior space must be used for cargo.
Because of safety regulations, the pilot, copilot and navigator can work only a certain number of hours, and they must sleep a certain number of hours. A flight might take two or three days. Therefore, they take turns sleeping in the berth. While the pilot is sleeping, the copilot flies the airplane. While the copilot is sleeping, the pilot flies the airplane. While the navigator is sleeping, both the pilot and the copilot take over his duties.