Congratulations! You've completed the first stage of your journey. You have your BeagleBone Black up and working. No gathering dust in the bin for this piece of HW. It is now ready to start connecting to all sorts of interesting devices in all sorts of interesting ways. One thing that is important to note: the system is not going to be nearly as stable as your PC or Mac. The HW and SW is new, and you're going to find yourselves coming back to this project from time to time to revive your board when it dies, because your SW has put it in some unrecoverable state.
Generally it is difficult to physically harm the board as long as you are only using the USB interface, so be brave, and remember, you often learn more from your failures than your successes.
