Click above to get retro games delivered to your door ever month!

  Some parts of the computer are able to transfer data to and from the
  computer's memory without passing through the CPU. This operation is
  called direct memory access, or DMA, and it is handled by a chip known
  as the DMA controller. The main purpose of the DMA controller is to
  allow disk drives to read or write data without involving the
  microprocessor. Because disk I/O is relatively slow compared to CPU
  speeds, DMA speeds up the computer's overall performance quite a bit.