Lives on blockchain and cannot be changed after deployment.

Solidity (Ethereum)

pragma solidity ^0.8.0;

contract SimpleStorage {
    uint public value;

    function set(uint _value) public {
        value = _value;
    }
}

Gas Fees

Gas = cost to run operations on blockchain

Gas fee = gas used × gas price

Contract Deployment

Deployment steps:

  1. Write Solidity contract
  2. Compile → bytecode
  3. Send transaction to blockchain
  4. Pay gas fee