Ethereum sharding is a scaling solution for the Ethereum blockchain that involves dividing the network into smaller, interconnected pieces called shards. Each shard can process transactions in parallel, increasing the capacity of the network and reducing congestion. This allows Ethereum to handle higher volumes of transactions and more complex smart contracts, making it more efficient and practical for everyday use cases. By implementing sharding, Ethereum is able to improve its scalability and speed up transaction times, while still maintaining its decentralized and secure nature.