Why? A lot of people can't fall asleep without some kind of ambient sound in the background. Alexa gives you a large selection of free sleep sounds — from a babbling brook to rain to simple white noise.
How? "Alexa, play thunderstorm sounds" or "Alexa, play rain sounds."
Pro Tip #1: Set a sleep timer. This will stop your ambient sounds from playing all night. Just say "Alexa, set sleep timer for 2 hours" to turn off your ambient sounds in 2 hours.
Pro Tip #2: Different ambient sounds turn off after different amounts of time. And some don't turn off at all unless you tell them to with an "Alexa, stop." So it’s always smart to set a sleep timer.