In the world of smart contracts, "gas optimization" is the effort to make contract code more efficient. Just like paying for shipping when sending a package, every action on the Ethereum blockchain requires "gas" as a fee.
Gas optimization means writing code that uses as little gas as possible. This is important because lower gas means cheaper transaction costs for users. This can be achieved by avoiding unnecessary calculations, using the right data types, and organizing code to be more concise. The goal is for smart contracts to run quickly, cheaply, and be accessible to many people.