What Is Ethereum?
ethereum.org defines It :
As 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.
Young ingenious fellow Vitalik Buterin proposed in 2013 that a single blockchain with the capability to be reprogrammed to perform any arbitrarily complex computation could subsume these many other eventually in 2014 he together with his partners began to work, with a vision to implement a general, fully trustless smart contract platform which you now know as Ethereum, The system went live on 30 July 2015, with 11.9 million coins “premined” for the crowdsale.
As per wiki: In 2016, as a result of the collapse of The DAO project, Ethereum was split into two separate blockchains — the new separate version became Ethereum (ETH), and the original continued as Ethereum Classic (ETC).The value of the Ethereum currency grew over 13,000 percent in 2017.
EVM: Ethereum Virtual Machine:
EVM is at the heart of Ethereum’s decentralized platform which can execute code of arbitrary algorithmic complexity. In computer science terminology, It is Called Turing complete. Techies can develop their own Dapp’s that gets executed on the Ethereum’s EVM using the language like JS, Python etc. Developers can create applications that run on the EVM using friendly programming languages modelled on existing languages like JavaScript and Python.
Similar to other blockhain ethereum works on P2P Network Protocols where each blockchain database is maintained and managed by multiple nodes each connected to the P2P network. Each node running their own EVM executes the same instructions, That’s why Ethereum is sometimes described evocatively as a “world computer”.
The ethereum nodes runs the EVM to build a decentralized consensus across the Blockchain network making Ethereum Network
CryptoCurrency
Ethereum has its own cryptocurrency named Ether which they also call as
The crypto-fuel for the Ethereum network
If any client executes any transaction on ethereum P2P network he pays in the form Ether to fuel the trasaction. Ether is also an incentive for encouraging developer to write a high quality dapp’s to minimize the cost which goes into writing a crappy code, it inspires the developers to maintain the coding standards apt for building a healthy ethereum ecosystem.