RISC stands for Reduced instruction Set Computing. It is at the heart of most microprocessors used today especially cell phones and the processors we use in our micro projects. It was a trend away from complex microprocessor instructions that had been the focus of a technology war to see who could make the most complex computers. But it turns out simpler is better and RISC proved it.
Check out this excellent article from CNET.com explaining RISC and why inventors John Hennessy and David Patterson have won computing’s most prestigious award.