What is stETH vs ETH?

Could you please explain the difference between stETH and ETH to me? I've been hearing about them but am still a bit fuzzy on the distinction. I understand that they both have something to do with Ethereum, but what are the key differences between them? Is stETH a derivative of ETH or a separate entity? How does the staking mechanism involved in stETH work? And why do some people prefer stETH over regular ETH? I'm eager to gain a deeper understanding of these two concepts.