Explain Conditional Types and their role in advanced utility types.

Conditional types allow you to select a type based on a condition, similar to a ternary operator in T extends U ? X : Y.

Conditional types add non-uniform mapping capabilities to the type system. They are the backbone of TypeScript's built-in utility types like Exclude, Extract, and ReturnType. When combined with the infer keyword, they allow you to 'reach into' a type and pull out a piece of it (e.g., getting the return type of a function or the element type of an array). This is essential for building highly adaptive library code that changes its behavior based on inputs.