Ethereum is a next-generation distributed cryptographic ledger that is designed to allow users to encode advanced transaction types, smart contracts and decentralized applications into the blockchain. Ethereum will support custom currencies or "colored coins", financial derivatives, and much more, but unlike many previous networks that attempted to accomplish the same thing Ethereum does not attempt to constrain users into using specific "features"; instead, the ledger includes a built-in Turing-complete programming language that can be used to construct any kind of contract that can be mathematically defined.
When the grand experiment that is bitcoin began, the anonymous wizard desired to test two parameters- a trustless, decentralized database enjoying security enforced by the austere relentlessness of cryptography and a robust transaction system capable of sending value across the world without intermediaries. Yet the past five years years have painfully demonstrated a third missing feature: a sufficiently powerful Turing-complete scripting language.
Up until this point, most innovation in advanced applications such as domain and identity registration, user-issued currencies, smart property, smart contracts, and decentralized exchange has been highly fragmented, and implementing any of these technologies has required creating an entire meta-protocol layer or even a specialized blockchain. Theoretically, however, each and every one of these innovations and more can potentially be made hundreds of times easier to implement, and easier to scale, if only there was a stronger foundational layer with a powerful scripting language for all of these protocols to build upon. And this need is what we seek to satisfy.