# Introduction

With the weather being great, you're not looking forward to spending an hour in a classroom.
Annoyed, you enter the class room, where you notice a strangely satisfying triangle shape on the blackboard.
Whilst waiting for your math teacher to arrive, you can't help but notice some patterns in the triangle: the outer values are all ones, each subsequent row has one more value than its previous row and the triangle is symmetrical.
Weird!

Not long after you sit down, your teacher enters the room and explains that this triangle is the famous [Pascal's triangle][wikipedia].

Over the next hour, your teacher reveals some amazing things hidden in this triangle:

- It can be used to compute how many ways you can pick K elements from N values.
- It contains the Fibonacci sequence.
- If you color odd and even numbers differently, you get a beautiful pattern called the [Sierpiński triangle][wikipedia-sierpinski-triangle].

The teacher implores you and your classmates to look up other uses, and assures you that there are lots more!
At that moment, the school bell rings.
You realize that for the past hour, you were completely absorbed in learning about Pascal's triangle.
You quickly grab your laptop from your bag and go outside, ready to enjoy both the sunshine _and_ the wonders of Pascal's triangle.

[wikipedia]: https://en.wikipedia.org/wiki/Pascal%27s_triangle
[wikipedia-sierpinski-triangle]: https://en.wikipedia.org/wiki/Sierpi%C5%84ski_triangle
