Sector Interleaves
The hard drives of modern PC,s no longer use sector interleaves, although they are still used by CD-ROMS. There was a time when the speed of the microprocessor was actually slower than the speed of the hard disk. This meant that the data transfer speed of the drive needed to be slowed to match the data handling ability of the CPU. Sector interleaves allowed the CPU to process data in pieces, allowing the CPU to finish with a piece of data before reading further.
A one to four ratio meant that no sectors were skipped. A one to four ratio meant that four sectors were skipped before any more data was read from the drive.
