ALU
	The Arithmetic/Logic Unit does the actual computation
		Each type of data has its own separate instructions ADDB    : add bytes   ADDBU   : add bytes unsigned ADDH   : add half words   ADDHU   : add halves unsigned ADD   : add words   ADDU   : add words unsigned ADDS   : add short decimal numbers ADDD   : add long decimal numbers
			Most computers have only about a 100-150 instructions hard wired