One of the three (3) spaceframe components that made up the Apollo spacecraft. During the mission, the Command Module served as life support and home for the three astronauts that made up the flight crew. It would orbit the moon during the landing phase, waitng to dock with the return vehicle from the lunar surface. It was also the component used to reenter the Earth's atmosphere. It would float on its inflatable skirt after splashdown for retreval by the US Navy.

the other two modules were:

The Service Module

The Lunar Excursion Module