Code: The Hidden Language of Computer Hardware and Software, 2nd Edition

Chapter Twenty-Two

Registers and Busses

Many of the routine operations of a computer involve moving stuff around, and by “stuff” I mean bytes of course. We experience this movement of bytes every time we load or save a file, when streaming music or movies, or when videoconferencing. Sometimes if those bytes don’t move fast enough, sound or video can freeze or become garbled. We’ve all been there.

On a more micro level, bytes also move within the central processing unit (CPU) itself. Bytes move from memory into the CPU, and into the arithmetic logic unit (ALU). Results from the ALU sometimes go back into the ALU for additional arithmetic or logical operations before eventually being moved into memory.

This movement of bytes within the CPU is ...