A compressed instruction set, or simply compressed instructions, are a variation on a microprocessor's instruction set architecture (ISA) that allows instructions to be represented in a more compact format. In most real-world examples, compressed instructions are 16 bits long in a processor that would otherwise use 32-bit instructions. It is distinct from the concept of , where any instruction can have any length; in a compressed set the instructions are alternative forms for existing 32-bit versions.