The Beacon Chain is Ethereum’s proof-of-stake (PoS) layer for verifying and settling transactions. It controls and coordinates the network of Ethereum stakers who help validate and secure the network in exchange for staking rewards.
The chain went live on December 2020. Before The Merge, it runs in parallel to Ethereum’s execution layer. However, it becomes the main Ethereum chain in September 2022. In addition, Beacon Chain also has also paved the way for sharding to help further scale Ethereum.
You can stake your ether (ETH) to get a portion of the staking rewards from a validator. The validator secures the network, processing transactions, and add new blocks to the blockchain.