NPR: The Making Of Apollo’s Command Module: 2 Engineers Recall Tragedy And Triumph.

“Look at a picture of the Apollo 11 launch and you’ll probably notice the rocket’s pointed tip and the fire coming from the five giant engines in the first stage of the 36-story-tall Saturn V rocket.

What you might miss is arguably the most important part of the entire thing: the command module.

It’s the tiny, gumdrop-shaped vehicle sitting just below the tip. It holds the astronauts, their clothing, sleeping bags, food and — along with a companion service module — all of the systems needed for a round-trip journey to the moon. It’s also the only piece of the spacecraft to complete the entire trip and splash down back on Earth.
[…]
On their way back, the astronauts sent one final transmission from space.

Collins had this to say: “This operation is somewhat like the periscope of a submarine. All you see is the three of us, but beneath the surface are thousands and thousands of others. And to all of them, I’d like to say thank you very much.””