Category of Functors
------------------------

If \\(\\C\\) is _small_ (\\(\\hom{\\C}\\) is a set).
All functors from \\(\\C\\) to some category \\(\\D\\)
form the category \\(\\mathrm{Func}(\\C,\\D)\\).

- \\(\\ob{\\mathrm{Func}(\\C,\\D)}\\): Functors \\(F:\\C→\\D\\)
- \\(\\hom{\\mathrm{Func}(\\C,\\D)}\\): _natural transformations_
- ∘: Functor composition

\\(\\mathrm{Func}(\\C,\\C)\\) is the category of endofunctors of \\(\\C\\).
