I first got the Ti-83 Plus calculator because it was required for a high school math class. Little did I really know how powerful of a calculator this really was. It has all the basic functions, like square roots and such, but my favorite feature is the ability to graph equations. The screen is fairly large, allowing you to easily see everything you need to. The coolest thing has to be the ability to download programs (and games!) to the calculator. You can write your programs in basic or assembly language, or download them from the web, and then transfer them to your Ti-83 Plus. It has a nice hard outer casing, too, to withstand all the punishment it takes from being hauled to classes everyday. I've had mine for over 5 years, and it's still as good as new. This may be an expensive calculator, but it is well worth it, and will last you for many years to come.