Do you know Why do we need space stations because Space stations are usually made up several modules that are sent into orbit one at a time, and taken assembled once in space. Space stations allow the crew in space for long periods of time in condition in zero gravity. While conditions in space capsules and the space shuttle are cramped, space stations are adapted for longer stay in space. Rocket or space shuttle brings supplies of air and food to the space station and often a replacement crew.
Some space stations, such as the Russian Mir, stayed up for many years and their crew remained in space for month at a time.