Bitcoin is a global payment network but there is no ownership company who control the network. Instead, different computers work with each other to maintain a collective transaction records which called a blockchain.
The main innovation that made this technology possible is a unique scheme for rewarding computers that provide their resources for building this shared ledger. Computers that participate then will be given a reward in created bitcoins. So there are a lot of who want to contribute computing power for Bitcoin transactions process.
Bitcoin network is specially created to verify and record payments. A programmer Vitalik Buterin realized that it is possible to create the same network as Bitcoin which could perform a much broader range of computational tasks. So, Ethereum is look like a distributed version of Amazon’s or Microsoft cloud computing platforms.
Ethereum can be used not only for making electronic payments but also for spending ether, the currency of Eethereum to run programs on the Ethereum network itself.
Ethereum is not a usual cloud computing network. Thousands of computers around the world perform every calculation at a time. And all data is public because the results of these calculations are stored on the Ethereum blockchain. So Ethereum is a very terrible choice for usual applications like running a web server.
Bot of course, Ethereum have some advantages. One of them is if a program starts running, no one can to modify or stop it. That means you can use Ethereum to make binding or long-term commitments which is why Ethereum programs are known as “smart contracts.”