How does rETH work?

Could you please explain to me in simple terms how rETH functions? I'm interested in understanding its inner workings, specifically how it's able to offer exposure to Ethereum staking rewards without the need for managing the staking process myself. I've heard it's a convenient way to earn passive income from crypto, but I'd like to have a clearer understanding of its mechanics. Could you also elaborate on the risks associated with investing in rETH and how it compares to other staking options? Thank you for your assistance.