It calculates Fibonacci For those who don't know what Fibonacci is: Fibonacci is an integer in the infinite sequence 1, 1, 2, 3, 5, 8, 13, … of which the first two terms are 1 and 1 and each succeeding term is the sum of the two immediately preceding.
I got the definition of Fibonacci from: https://www.merriam-webster.com/dictionary/Fibonacci%20number
