STS-133 was an ISS assembly flight. Payload included the Permanent Multipurpose Module Leonardo, which was left permanently docked to one of the station's ports. The shuttle also carried the third of four ExPRESS Logistics Carriers to the ISS, as well as a humanoid robot called Robonaut.
The International Space Station programme is tied together by a complex set of legal, political and financial agreements between the sixteen nations involved in the project, governing ownership of the various components, rights to crewing and utilization, and responsibilities for crew rotation and resupply of the International Space Station. It was conceived in 1984 by President Ronald Reagan, during the Space Station Freedom project as it was originally called.