A functor is the mapping from 1 object to another object, with a “Select” ability to map 1 morphism to another morphism. A [bifunctor](http://en.wikipedia.org/wiki/Functor#Bifunctors_and_multifunctors

If F: C → D and G: C → D are both functors from categories C to category D, the mapping from F to G is called and denoted

In category theory, is a ) from category to category. Giving category C and D, functor F from

) is an important algebraic structure in category theory. A monoid M is a set M equipped with a binary operation ⊙ and a special element

Category theory is a theoretical framework to describe abstract structures and relations in mathematics, first introduced by and [Saun

All the previous parts demonstrated what can do – defining functions to model the computing, applying functions to execute the computing

p is the ) (aka invariant point) of function f :

In lambda calculus, the primitive is function, which can have free variables and bound variables. was introduced by [Moses Schönfink