What's A Sprinkler?

OK, so it's pretty well-known that we aren't lawn people. At all.
A byproduct of this is that our kids don't know what a sprinkler is
or how it works:

Charlie is holding a mini watering can over the water going up.
Not so effective at filling the can!
Max's turn:

Is there any in there yet?

The whole 'gleefully running through' the sprinkler that most
kids do doesn't even occur to them.
One of these days I'll have to show them how it's done!