What are generics in TypeScript? Why are they useful?

Answer

Generics allow creating reusable components that work with a variety of types while maintaining type safety.

function identity<T>(arg: T): T {
  return arg;
}

const numberIdentity = identity<number>(42); // Explicit type
const stringIdentity = identity("Hello"); // Type inferred

Why Useful:

Generics prevent duplication and allow functions or classes to operate on different types without losing type information.