Import

The import statement is used to import local and external files in Solidity.

Internal

use of a relative path (./). like the example below

// import Hello.sol from current directory import "./Hello.sol";

External

You also can import from GitHub by copying the URL below

import "https://github.com/owner/repo/blob/branch/path/to/Contract.sol";

Import a Library

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";