by Robin Rowe 11/11/05
RPN is a stack-based method of data entry used by many HP calculators.
http://www.hp.com/calculators/news/rpn.html
RPN uses fewer keystrokes and performs complex calculations without resorting to parentheses, but does have a slight learning curve if you've never seen it before.
If you like RPN you probably also like the programming language Forth. Because it is so small, Forth is used in embedded systems, such as the BIOS of all modern Macintosh computers.
http://www.embedded.com/shared/printableArticle.jhtml?articleID=9900749
Kforth is an open source implemention in C++ and portable across Linux and Windows (330kb download).
http://ccreweb.org/software/kforth/kforth1.html
Glasgow doesn't currently use Forth.
http://cinepaint.bigasterisk.com/GlasgowDocumentation