typescript-interface-vs-type

The difference between interface and type in TypeScript is that interfaces are generally preferred for defining object structures and extending classes, while type aliases are required for unions, mapped types, conditional types, and tuples.

You should use a type alias instead of an interface in TypeScript when defining union types, mapped types, conditional types, or tuples, as these features are not supported by the interface keyword.

You should use interface extends instead of type intersections in TypeScript because it provides improved error reporting during compilation and better performance when resolving complex object structures.

To choose between interface and type for a TypeScript object definition, use interface for standard object shapes and class implementations, and use type when you need advanced features like unions or mapped types.

No, you cannot use TypeScript interfaces for union types. You must use the type keyword to define union types, mapped types, conditional types, and tuples in your TypeScript codebase.