The programming paradigm that emphasizes functions and immutable data is known as functional programming. This paradigm focuses on the evaluation of functions rather than the execution of commands and emphasizes the use of pure functions that avoid side effects. By treating computation as the evaluation of mathematical functions, functional programming facilitates reasoning about code behavior and promotes reusability. Examples of functional programming languages include Haskell and Scala. This approach can lead to more predictable and maintainable code, particularly in concurrent and parallel computing environments.