Ethereum is completing a major upgrade to its network, as it will be migrating from Proof-of-Work (PoW) governance into proof of stake. This represents an important milestone for Ethereum and opens up many new possibilities in future applications that can utilise this Proof-of stake consensus layer!
Following the Merge, PoW miners will no longer validate transactions on the network and mine new tokens. This responsibility will instead be done through nodes called validators.
You can read more about Ethereum 2.0 here.