Divide-and-Conquer is a recursive technique to solve problems.

Quicksort is a Divide-and-Conquer algorithm

To solve a problem using Divide-and-Conquer, there are 2 steps:

1. Figure out the base case (the simplest possible case)
2. Divide or decrease the problem until it becomes the base case.

Divide-and-Conquer is not an algorithm. It’s a way to think about a problem.

When you are writing a recursive function that has an array as part of the problem, the base case is often an empty array or an array with one element.

Recursive algorithms are used on functional programming languages - since they do not have loops. So, a good understanding of recursion makes functional languages easier to learn.

If you want to dive into recursion, use may try Haskell - a functional programming language.