This site is for programmers. But it is not about programming languages or tutorials or whatever. It is about the methodology of programming. Yes, programming is not just about going in and coding some stuff, especially for programs which are huge in size and feature. Just imagine being stuck in one route without any way to turn back if you need. This methodology helps delivers the software you need as you need it, not just about providing features somewhere along the line. I know it is a bit confusing but a lot of software house have used their methodology and have found it to be successful in the long term. It also helps emphasis teamwork - something which larger programs relies on. And by keeping the design clean and simple, it helps to ensure troubleshooting later on (if needed). And the best part, Extreme programming has very simple rules to follow. Check out their flowchart to understand how it actually goes. Good luck.