ELI5: Explain Like I'm 5

Analytic function

An analytic function is like a magical formula that can be used to calculate things in a very special way. It works for certain types of numbers, called complex numbers, which are like regular numbers, but with two parts instead of one. Think of a complex number like a toy airplane with two propellers: one propeller spins in the up and down direction, while the other spins left and right.

When we use the magical formula of an analytic function, we can turn these complex numbers into other complex numbers in a really neat way. And if we keep applying this formula over and over, we can create a whole bunch of new complex numbers which all relate to each other in special ways. It's kind of like building a tower out of blocks, but instead of blocks, we use complex numbers and the formula of the analytic function.

Now, the most amazing thing about the analytic function is that it's very smooth and nice to work with. Just like how skating on ice is much easier than walking on rough ground, using an analytic function to create new complex numbers is much easier than using other methods. And because it's so smooth, we can do all sorts of fancy tricks with it, like finding where the complex numbers behave badly or calculating really complicated integrals.

In the end, the analytic function is just a really powerful and magical tool for dealing with complex numbers. And even though it might seem a bit tricky at first, with enough practice and study, we can learn to use it like a pro!