Preferred calculator program language

[David Hayden]

As with others, for me it depends on the task at hand.

But I'll give a shout out for RPN keystroke programming because it's so easy to learn, so easy to teach and so easy to use on a calculator. The big drawback is that it's so hard to read, at least for me. We're all used to infix notation so it's hard to understand an expression in RPN's post-fix.

RPL is a great combination of power in a language whose implementation is light weight.

HPPPL is a Real Language.