Unlambda Description
Unlambda can be described as a programming language. There is nothing extraordinary there. Unlambda's uniqueness is its unexpected intersection of two marginal languages. Functional programming languages are a group that includes Scheme (a Lisp dialect). This means that the primary object that is manipulated by the language, and indeed the only one for Unlambda, is the function. Unlambda, on the other hand, uses a functional approach in programming. Functions are the only objects it can manipulate. Each function takes a function and returns it. Unlambda has many built-in functions, including a binary "apply", which returns a function. The most important are the K and S combinators. Unlambda doesn't have variables so user-definable functions can be created but not saved or named.