3 ms·Obligatory but futile plug for HP RPN calculators.by macintux 4y agoObligatory but futile plug for HP RPN calculators.cfraenkel 4y agoSeconded. But I'm afraid RPN is an endangered species. Who's learning it anymore?kccqzy 4y agoProbably every computer science student learns it in order to implement something useful after learning about the stack.