What is Ethereum?\\r\\nEthereum is an open blockchain platform that lets anyone build and use decentralized applications that run on blockchain technology. Like Bitcoin, no one controls or owns Ethereum – it is an open-source project built by many people around the world. But unlike the Bitcoin protocol, Ethereum was designed to be adaptable and flexible. It is easy to create new applications on the Ethereum platform, and with the Homestead release, it is now safe for anyone to use those applications.\\r\\nEthereum Virtual Machine:\\r\\nEthereum is a programmable blockchain. Rather than give users a set of pre-defined operations (e.g. bitcoin transactions), Ethereum allows users to create their own operations of any complexity they wish. In this way, it serves as a platform for many different types of decentralized blockchain applications, including but not limited to cryptocurrencies.\\r\\n\\r\\nHow does Ethereum work?\\r\\nEthereum incorporates many features and technologies that will be familiar to users of Bitcoin, while also introducing many modifications and innovations of its own.\\r\\nthe basic difference between these is that human users control EOAs - because they can control the private keys which give control over an EOA. Contract accounts, on the other hand, are governed by their internal code. If they are “controlled” by a human user, it is because they are programmed to be controlled by an EOA with a certain address, which is in turn controlled by whoever holds the private keys that control that EOA. The popular term “smart contracts” refers to code in a Contract Account – programs that execute when a transaction is sent to that account. Users can create new contracts by deploying code to the blockchain.\\r\\n\\r\\nContract accounts only perform an operation when instructed to do so by an EOA. So it is not possible for a Contract account to be performing native operations like random number generation or API calls – it can do these things only if prompted by an EOA. This is because Ethereum requires nodes to be able to agree on the outcome of computation, which requires a guarantee of strictly deterministic execution.\\r\\n\\r\\nLike in Bitcoin, users must pay small transaction fees to the network. This protects the Ethereum blockchain from frivolous or malicious computational tasks, like DDoS attacks or infinite loops. The sender of a transaction must pay for each step of the “program” they activated, including computation and memory storage. These fees are paid in amounts of Ethereum’s native value-token, ether.