- Architecture of a hard disk:
Notes:
- Platters are
2-sided and
magnetic
- Platters rotates
(about 10000 RPM)
- All disk heads move at the same time (in or out)
I found a cool animated gif at this website ( click here ) that illustrate the operation of a hard disk:
- Platters are
2-sided and
magnetic
- Topview of a
platter:
Notes:
- Platter has
circular tracks
- Tracks are
divided into
sectors
- Sector =
the unit of
write operation for a
disk
However:
- Sector is too small to be efficient
- Computer systems read/write a block (= multiple sectors) at once.
- Gaps are non-magnetic and used to identify the start of a sector
- Platter has
circular tracks
- Terminology:
cylinder
Cylinder = all tracks at the same distance from the center
(Disk head does not need to move when accessing (read/write) data in the same cylinder)