This calculator is basically perfect. I use it for my math classes, and I have yet to find any situation that it will not accomodate me for. My experiences with this calculator at first confused and frustrated me, but since having learned how it functions, it has augmented my ability to learn math many times over. For this calculator, you really want to save the owner's manual or else you will be lost forever in the midst of functions that you don't understand. The only concievable problem that a person can find with this calculator is its formidable size. It might fit in a person's jean's pocket if one shoved it in, but, generally, it belongs in a backpack with all of your schooling supplies. This is the most perfect school calculator I know of, and it's lasted me about three years now. I've dropped this thing so many times and yet it's stayed intact and perfectly functionable. In addition, to graphs, functions, permutations, holes, asymptotes, radian measurements, general and expert level calculus functions, and everything else, this calculator also holds games. I have tetris for instance, and it carries me through the day sometimes. Also, you can program this calculator to do certain functions. But, that requires time and effort, and even I haven't done that yet. Other than that, I love this calculator.