Yul is an intermediate programming language that can be used to write a form of assembly language inside smart contracts

Yul is an intermediate programming language that can be used to write a form of assembly language inside smart contracts. Although we often times see Yul used inside smart contracts, you can write a smart contract entirely in Yul. Understanding Yul can level up your smart contracts and allow you to understand what is going on under the hood in solidity, which in turn can help you save user’s gas costs. We can identify Yul in a smart contract with the following syntax.