Type Aliases

A type alias gives a name to any type — not just object shapes like an interface, but also unions, primitives, or anything else.

type ID = string | number;
type Point = { x: number; y: number };

function printId(id: ID) {
    console.log(id);
}

For plain object shapes, interface and type are largely interchangeable — the difference between them is covered in Level 2.