This is a sample project made for the purpose of demonstrating git, a version control system, and GitHub, an online git service provider.
People believe that the hardest part of software development is writing the code. That's true in the very beginning of your career, but the ability to write good code is not all it takes to be an effective engineer. Software is a tool, a very complex tool, and the effectiveness of the tool depends very much on how well it is documented, and the soundness of its design.
Which is where Version Control Systems come in. They are systems, software-based or otherwise, that allow us to trace the life of a tool over all the stages of its design. And really, when you think about it, naming your file final_version_1.xyz is version control too, it's just not a perfect implementation.
Git has its own flaws, but it is a lot more intuitive than final_version_1.xyz, and certainly easier to debug and find solutions for on StackOverflow. And GitHub is what we're using here, but there are many other service providers each with their own special sauces and terms & conditions, so do please explore them all before you settle on one. (Although odds are you'll like GitHub the most.)