Rain sounds for sleep.

Rain puts people to sleep for a boring, wonderful reason: nothing in it ever changes. A real downpour keeps the same low shape for hours — no chorus, no drop you're waiting for. Your hearing has nothing new to report, so your brain stops listening, and a brain that has stopped listening is most of the way to asleep.

Rain also covers the sounds that were keeping you up — the fridge, the street, the house settling. They don't go away; they stop mattering. Under rain, a creak is furniture. Without it, a creak is a story.

Some rain is too bright for sleep — light patter with a hiss in it, like static. Dark rain is the other kind: lower, slower, heavy on the roof. It's the rain you hear from inside a warm car, the kind that makes you drowsy just remembering it.

That's why rain is the sound most people come back to. It asks for nothing and it changes nothing. Press it on a night when your thoughts are loud, and it carries them — at the same low volume — until they're gone.

It's waiting above, one tap away. Fifteen quiet minutes, low and steady the whole way through.