Instruction set facts for kids

Kids Encyclopedia Facts

An instruction set is a list of all the instructions, with all their variations, that a processor can execute.

Instructions include:

  • Arithmetic such as add and subtract
  • Logic instructions such as and, or, and not
  • Data instructions such as move, input, output, load, and store
  • Control flow instructions such as goto, if ... goto, call, and return.

An instruction set, or instruction set architecture (ISA), is the part of the computer architecture related to programming—including the native data types, instructions, registers, addressing modes, memory architecture, interrupt and exception handling—and external I/O. An ISA includes a specification of the set of opcodes (machine language), the native commands implemented by a particular central processing unit design.

Instruction set architecture is distinguished from microarchitecture, which is the detailed description of the system that is sufficient for completely describing the operation of all parts of the computing system, as well as how they are inter-connected and inter-operate to implement the ISA.

Computers with different microarchitectures can share a common instruction set. For example, the Intel Pentium and the AMD Athlon implement nearly identical versions of the x86 instruction set, but they are very different in internal designs.

Other pages

Instruction set Facts for Kids. Kiddle Encyclopedia.