Calm Sleep Sounds is a feature within the Calm app, a popular meditation and sleep app. It offers a variety of ambient sounds designed to help users fall asleep and stay asleep. These sounds are typically nature-based, such as rain, waves, or white noise, and are often combined with other calming elements like gentle music or ambient soundscapes. The goal is to create a relaxing auditory environment that masks distracting noises and promotes relaxation.