The Apollo Guidance Computer was a special type of computer used by the Apollo astronauts for their trips (missions) to the Moon. This computer was very advanced for its time, and it helped guide the Apollo spacecraft, like a GPS does for a car today. It was able to calculate the position of the spacecraft in space, figure out the right course to take, and make sure the craft stayed on track. By helping the astronauts fly to the Moon, the Apollo Guidance Computer made the first human mission to the Moon possible!