Hard disk drive
part · 1956 · Digital age
Magnetic platters with heads (IBM 350).
What it is made of
- Electric motor — has part. A spindle motor.
- Ball bearing — has part. Bearings (later fluid-dynamic ones).
- Neodymium magnet — has part. The head actuator.
Principles and materials it uses
- Magnetism — uses. Magnetic recording.
- Aluminium — is made of. The platters are aluminium or glass.
- Cobalt — is made of. The magnetic layer is a cobalt alloy.
Where it is used
- Personal computer — is part of. A hard disk.
- Virtual memory — is used in. Paging to disk.
- File system — is used in. Partitioning the disk.
History: what it evolved from and what it influenced
- Solid-state drive — evolved into. A replacement for the hard disk.