Opcode
Opcodes will vary in capability and 'value' depending on the computer to which they belong, as they are hardware dependent. For instance, the opcode for STORE as expressed in Hex could be FA for one machine and 02 for another. Some opcodes will not be available on some computers. In general, there are two approaches toward building instruction sets. A reduced instruction set computer (RISC) offers less possible opcodes in favor of increasing speed for simple processes. Complex instruction set Computing (CISC) offers more opcodes in favor of increasing speed for complex processes.