The International Space Station (ISS) is a modular space laboratory in low Earth orbit, jointly operated by NASA, Roscosmos, ESA, JAXA, and CSA. Launched beginning in 1998, it has been continuously inhabited since November 2000 and supports cutting-edge research in microgravity, Earth observation, and space technology, while fostering international cooperation.
Source: nasa.gov
15/04/2002

The International Space Station (ISS) is being fitted with a backbone. During the present visit of Space Shuttle Atlantis, astronauts are installing a huge truss on the growing space outpost. The truss is over 13 meters long and about 4.5 meters wide. Dubbed Starboard 0, or S0 (pronounced S-Zero) for short, the truss will route electricity, vent excess heat, and allow for future ISS expansion. Pictured above, the truss was lifted out of the shuttle's cargo bay by the station's robotic Canadarm2.