What are TypeScript utility types?

TypeScript ships with built-in utility types that perform common type transformations. Key ones: Partial<T> — makes all properties of T optional (useful for update operations). Required<T> — makes all properties required (opposite of Partial). Readonly<T> — makes all properties readonly. Record<K, V> — creates an object type with keys of type K and values of type V. Pick<T, K> — creates a type with only the specified properties K from T. Omit<T, K> — creates a type excluding the specified properties K from T. Exclude<T, U> — removes types from T that are assignable to U. Extract<T, U> — keeps only types from T that are assignable to U. NonNullable<T> — removes null and undefined from T. ReturnType<T> — extracts the return type of a function type. Parameters<T> — extracts parameter types as a tuple. These utility types are built using TypeScript's advanced type features (mapped types, conditional types) and are essential tools for type manipulation.