QR decomposition

Okay kiddo, imagine you have a really big puzzle, like a thousand pieces big. And you want to solve it, but it's so hard and confusing because there are so many pieces!

QR decomposition is like breaking up that big puzzle into smaller, easier-to-solve pieces. You take the puzzle and divide it into two parts: the first part (let's call it Q) is made up of all the straight edge pieces and the second part (let's call it R) is made up of all the remaining pieces.

Now, Q will help you to understand the overall structure of the puzzle, like where the corners and edges are, and where the pieces might fit together. R will help you solve the smaller parts of the puzzle, like finding the right piece to go in a specific spot.

When you put Q and R back together, you have solved the whole puzzle! QR decomposition is like a shortcut for solving a big, complicated problem by dividing it into smaller, more manageable parts.