The Official Intro to Solidity

(solidity.readthedocs.io)
Solidity — Solidity 0.5.4 documentation
solidity.readthedocs.io

Solidity — Solidity 0.5.4 documentation

Solidity is an object-oriented, high-level language for implementing smart contracts. Smart contracts are programs which govern the behaviour of accounts within the Ethereum state.

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