Chapter 6 - Storage Devices (1.1) Flashcards
Why is secondary storage needed?
Retains components of the computer when turned off, which means that no data is lost.
What are the 3 types of storage devices?
- Hard disk
- Optical media
- Solid state disks
How does a Hard Disk work?
They rotate magnetic platters at high speeds under a read/write head on an arm, combination of the arm and rotating platter allows the read/write head to access any part of the platter
what is an advantage of hard disks?
Huge capacity as they have smaller and denser surface area
What is a disadvantage of hard disks?
- Less portable than other storage devices
- Slow data transfer speeds
How does an Optical Disk work?
They’re read from/written to using lasers, binary info is represented by portions of the disc that either reflect or scatter the laser light
How much data can CD-ROM hold?
around 700MB of data
How much data can a Blu-ray disk hold?
around 50GB of data
What is an advantage of optical disks?
Cheap to produce and very portable
What is a disadvantage of optical disks?
Can be corrupted or damaged easily by excessive sunlight or scratches
What are some advantages of solid-state disks? (6)
- Faster access speed
- Consumes less power
- Less susceptible to damage
- Silent in operation
- Lighter
- More portable
What are some disadvantages of solid-state disks? (3)
- Relatively low capacity
- Expensive
- Limited lifespan
What are the 2 kinds of internal memory?
random access memory and read only memory
What is RAM used for?
Storing programs and data that are being used, as it’s volatile the contents are lost when computer is turned off
What is ROM used for?
Stores programs that need to be permanently in memory, as it’s non-volatile the contents are not lost when computer is turned off
