>>23254The CPU contains a register called the instruction pointer (abbreviated IP)
which contains a number. The number in the IP is the memory address at which
the next instruction is to be performed. IP is incremented with each
instruction, and in the event of a JMP instruction (a jump instruction, which
tells the CPU to jump to another location and start running the instructions
there), IP is set to the jump location and then the CPU continues on its way
from there. The CPU's instructions are sometimes called "opcodes". They are
simply strings of binary 1s and 0s which together form an instruction. For
example, on a standard Intel 80x86 CPU (such as a 486 or Pentium), the opcode
90h (or 10010000 binary) is a NOP (no operation) opcode. NOP is the simplest
instruction in any CPU, and it simply means to do nothing and go on to the
next instruction. If a cell in RAM or ROM contains this opcode and the CPU
executes it, it will perform a NOP (in other words, it will do nothing) and
then IP will be set to the next memory cell. (On some computer platforms, the
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