The Fibonacci sequence is a series of numbers in which each number is the sum of the two that precede it. Starting at 0 and 1, the first 10 numbers of the sequence look like this: 0, 1, 1, 2, 3, 5 ...

Put simply, the Fibonacci sequence is a series of numbers which begins with 1 and 1. From there, you add the previous two numbers in the sequence together, to get the next number.