Every satellite launched into space comprises a 'payload' and a 'bus'. The payload is all the equipment a satellite needs to do its job - the tools for the task. This can include antennas, cameras, radar and electronics. Each satellite will carry its own unique set of instruments or technology relevant to the mission. The payload for a communications satellite would require large radio antennas to receive and transmit television or telephone signals to Earth. A disaster monitoring satellite might contain cameras to take photographs of the land below.
