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LEARN SOLIDITY LESSON 1: Contracts. Pragma. State Variables. Integers

LEARN SOLIDITY LESSON 1

Contracts. Pragma. State Variables. Integers



An empty contract named HelloWorld would look like this:
All solidity source code should start with a "version pragma" — a declaration of the version of the Solidity compiler this code should use. 

State variables are permanently stored in contract storage. This means they're written to the Ethereum blockchain. Think of them like writing to a DB.
pragma solidity >=0.5.0 <0.6.0;
contract HelloWorld { uint myUnsignedInteger = 10;

}
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