Title: Computer Science / Section 1: Components of a computer / Chapter 6: Storage devices

Q: Explain Hard drives
A: Uses a reading head and writing head to read/write data using magnetism to flip and read magnetic switchs on a spinning disk - mechanical
- Magnetic
- Non volatile
- Random access
- 15ms latency
- Internal controller
- Fail if the head crashes
- Moderate cost
- Backups, older PCs

Q: Explain optical disks
A: Laser burns dips in a reflective surface then a less powerful laser can see which dips reflect light and not to read the 1s and 0s
- Laser/Optical
- Non volatile
- Random access
- 150ms latency
- External controller
- Scratchable
- Cheap cost
- Long term archives, media distrubution (Film, TV, Game)
- CD (700MB), DVD (8GB), BD (50GB)

Q: Explain Solid State/Flash storage
A: - Solid State
- Non volatile
- Random access
- No latency
- Internal controller
- Circuitry can fail
- High cost
- Used in most modern PCs and mobile devices
- SSD, Flash drive

Q: Explain RAM storage
A: - Volatile
- No latency
- Internal controller
- Very high cost
- Memory
- SO + DDR1 - 5

Q: Explain tape storage
A: - Magnetic Tape
- Non volatile
- No random access
- Very slow latency
- External controller
- Very cheap
- Long term archival