FizzBuzz is or used to be an interview question. The goal of this test is to first figure out if a person can code at all and secondly how well a person can solve a simple problem.
The FizzBuzz test is base on a game of the same name. The goal of the game is to go around a circle of players saying a number starting from one. If the number is divisible by three you say Fizz instead of the number, if it's divisible by five you say Buzz and if it's divisible by both you say FizzBuzz.
This coding challenge is exactly the same: You create a program that output numbers from one to a hundred replacing numbers by the FizzBuzz rules.