You’ve been busy learning here, building up your knowledge and skills through your nanodegree work. But, what’s actually happening inside your head to enable this growth? Well, each time you think about something, you activate particular neural pathways in your brain, and that activation strengthens the pathways themselves. As a simple example, if I just learned basic addition so that I can figure out that three plus two equals five, the more I do problems similar to this like, one plus six equals seven, the easier it will be for me to remember how to add digits together. Essentially, we grow our knowledge and make it easier to access the more we recall relevant information. Research also shows that applying new learning in different contexts makes it even stronger, and it allows you to retain it better. So, if I move from problems like three plus two equals five to trying out something like 4 plus 20, plus 1, plus 6, I have the opportunity to apply my addition skills in a new context with bigger numbers and more things to add up. This will make my brain distill the core concepts necessary for understanding how addition really works, which means that in the future, when faced with even trickier addition problems, I’ll have a strong foundation to tackle those challenges. This is exactly what we want to prepare you to do, albeit with much tougher problems. Our job at Udacity is to help you build deep knowledge and flexible skills that you can apply to all sorts of novel problems in the future. In order for that to happen your brain needs to actively engage with problems, questions, and ideas that will push it to grow in the desired direction