Bytecode

ABIs

In Ethereum, an ABI (Application Binary Interface) is a standardized way for interacting with smart contracts. It defines how data should be encoded and decoded when being sent to and from a contract on the Ethereum blockchain.

Simple Solidity contract

// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.7.0 <0.9.0;

contract Sum {
    function sum(uint a, uint b) public pure returns (uint) {
        return a + b;
    }
} 

Corresponding ABI

[
	{
		"inputs": [
			{
				"internalType": "uint256",
				"name": "a",
				"type": "uint256"
			},
			{
				"internalType": "uint256",
				"name": "b",
				"type": "uint256"
			}
		],
		"name": "sum",
		"outputs": [
			{
				"internalType": "uint256",
				"name": "",
				"type": "uint256"
			}
		],
		"stateMutability": "pure",
		"type": "function"
	}
]

Try creating your own at https://remix.ethereum.org/