franjo.sarcevic@live.deBetween any two sets with sufficiently rich structures one can establish functions/maps with a purpose to transform in a way one structure into another. Ordinary analytic functions can be approximated by Taylor polynomials, expressed by Taylor series etc, which gives a discretized model of a continuous quantity. These issues are addressed by a discipline called calculus. In analogy with this ordinary calculus, but on a much more abstract and complex level, during 1990s and 2000s calculus of functors - also known as Goodwillie calculus - has been devised. The calculus of functors deals with the questions of approximating functors between two categories. Frequent notions in that theory are that of analytic functor, derivation of a functor, Taylor approximation, Taylor tower, convergence etc. The functor calculus has three main branches, depending on which categories one takes and what conditions one sets for functors. In this talk, I will present the idea of manifold calculus of functors, trying to be as intuitive as possible. I will also present the main results of that theory, as well as my work in that field.