This is an RPN (Reverse Polish Notation) calculator with many useful features. The RPN expression evaluation is superior to Algebraic. It just takes getting used to. There is a four register stack and ten memory locations for number storage.
This calculator has many useful functions:
1) Normal scientific functions, like trigonometry, logarithmic and others.
2) Programmable: Included editor, debugger, and many program control functions. This graphics system is also tied to the programability of the calculator.
3) A very ingenious parameter converter.
4) Has a graphics ability. Modes: Linear (includes linear regression) Parabolic, Points, and Polar modes.
5) Includes an amortization calculator with ability to export amortization parameters.
6) Extensive help available and it is context sensitive allowing quick help for any key.
7) Programmed to make extensive use of a bluetooth keyboard, if attached.
8) Can do matrix calculations. Inverse, multiply, add/subtract and will calculate determinate.
9) Has a Periodic Table reference function that can be very detailed.
10) Makes use of iOS 10s universal clipboard capability.
In short, this is a very useful calculator and can do complex arithmetic, but it is also very handy at doing just simple arithmetic.