Hello Everyone, In the calculator world HP has hit some Home Runs in its time. Starting back with the original HP 35 to the little HP 25 to the HP 67 to the HP 41cx and the well used HP 48 gx. Ever one i just mention was well used in the surveying world and many more that i left out. Some of these even came with surveying programs. Now the programming is left up to us. When i started writing RPN in 1976 I was amazed how this made my math much easier to do. Plus to know how correct it was. Then came the HP 41cx with the Survey Pac. , this was a dream come true. Then it was not to long the HP 48 appeared, then final the HP 48 gx with its program cards and the ram cards to back it up. SMI and TDS play a big part in the following years. If you used a Data collector that was a calculator, this was the dual role that it played. now the world has changed to more computer type collectors in the field. This also leaves the surveyor in the field wishing he or she had a calculator. This is how this gap is filled with the only RPN calculator made today. Some in the world do not use a RPN logic calculator. HP has even went so far as to have both modes for those who do not. There is nothing wrong with Algebraic expressions ,I just like RPN logic. There are less steps in programming. But on with this story on how this little calculator stack up with the models that came before it. Lets first look at programming, and this list may surprise you.Even for those who write RP Lisp. and the new HP PPL Language for HP Prime. The HP 35s. will surprise you.