Tuples are great additions to C#. They're simple immutable structures made of a small number of members organized in a specific order. For example, a point on a plane could be represented as a pair of X and Y coordinates, or a person's name could be represented as a title, first, middle and last names. If the types are that simple, and have no custom logic associated with them, using a tuple looks like a lightweight and simple implementation that requires a lot less effort than a simple class or struct. Dynamic and functional languages have long enjoyed tuples, of course, but I like how the C# implementation manages to stay true to the core tenets of the language, in particular type safety.