In Ethereum you have the possibility to create Dapps that are decentralized applications that use the ethereum blockchain to work.
Smart contracts are used for the functioning of Dapps, as they exchange payment information with the blockchain.
Ethereum Virtual Machine EVM was created by the Ethereum foundation and is the official platform for creating Dapps.
The EVM uses the programming language called SOLIDITY which is a new language similar to C ++ or C #, very light is simpler.
Ethereum is the platform that has more Dapps inside as the first to have introduced them.
Smart contracts use the ERC20 protocol which is Ethereum’s technical standard.
There is the possibility of exchanging smart contracts of other blockchains on ethereum enough that they have the ERC20 protocol.