What is a Solidity contract structure?

A Solidity contract is similar to a class in OOP. Basic structure: // SPDX-License-Identifier: MIT\npragma solidity ^0.8.0;\ncontract MyToken {\n // State variables (stored in storage)\n string public name;\n uint256 public totalSupply;\n mapping(address => uint256) public balances;\n \n // Events\n event Transfer(address indexed from, address indexed to, uint256 amount);\n \n // Constructor (runs once at deployment)\n constructor(string memory _name, uint256 _supply) {\n name = _name;\n totalSupply = _supply;\n balances[msg.sender] = _supply;\n }\n \n // Functions\n function transfer(address to, uint256 amount) external returns (bool) {\n require(balances[msg.sender] >= amount, "Insufficient balance");\n balances[msg.sender] -= amount;\n balances[to] += amount;\n emit Transfer(msg.sender, to, amount);\n return true;\n }\n}. Key elements: SPDX license identifier (good practice), pragma version, state variables, events (for logging), constructor (deployment init), and functions (with visibility: public/private/internal/external).