Explain Return Like I'm Five

So, we can think of a function as a box that does things, right? We put things into the box and the box acts upon them.

For example, imagine a box called "plus". The plus box will add together whatever things we happen to put into it. Like this:

        ┏━━━━━━━━━━┓
1 ────> │ ───┐            ┃
        ┃    1  +  2      ┃
2 ────> │ ─────────┘      ┃
        ┗━━━━━━━━━━┛

Right now, we've used "plus" to add 1 and 2. We have 3, but it's just sitting in our box. We want 3 to be able to get out of the box:

        ┏━━━━━━━━━━┓
1 ────> │ ───┐            ┃
        ┃    1  +  2 ────>  3
2 ────> │ ─────────┘      ┃
        ┗━━━━━━━━━━┛

The return keyword is what allows us to get the 3 out of the box. Now, we give our box 1 and 2, and get 3 in return.