What is Ethereum?
Ethereum is an open-source, public, blockchain-based distributed ledger featuring smart contract (scripting) functionality. It enables developers to build blockchain applications with business logic that execute in a trustless environment, while leveraging the high availability of the Ethereum network.
Why does it matter?
Because it opens the door to a global financial system where an Internet connection is all you need to access applications, products and services that operate in a trustless manner. Anyone can interact with the Ethereum network and participate in this digital economy, without the need for third parties and without the risk of censorship.