How does stETH work in Lido?

Could you please explain, in simple terms, how stETH operates within the Lido ecosystem? I'm curious about the mechanics behind it and how it fits into the larger cryptocurrency and finance landscape. Could you elaborate on the process of staking Ether and how stETH represents those staked tokens? Additionally, I'd like to know about the potential risks and rewards associated with staking through Lido and holding stETH.