Unit 3 Storage Devices and Media Flashcards
What is a definition of Data Storage?
Where data is put in a ‘known’ place which we can come back to later and get the data back
Where can data be stored temporarily?
RAM - computer memory
- volatile - data is erased when computer is switched
off
- used to store data that is currently in use
- very fast reading/writing data
Where can data be stored permanently?
Backing storage devices
- non-volatile
- used to store data long term
- slower reading/writing of data
How is data stored and read?
By Serial Access (sequential)
By Direct Access (random)
What is Serial Access?
Data that is accessed at the beginning and gone through in order until the required information is found
e.g. video cassettes, music cassettes
What is Direct Access?
The computer is able to calculate where the data is stored and can go straight to it. e.g. hard disks, CDs, DVDs, USBs, Flash memory
What is storage media?
Storage media are devices that hold data (not store)
What types of storage media are there?
Magnetic media - holds data magnetically e.g. fixed hard drive, portable hard drive
Optical media - CD-R, CD-ROM, DVD-RW
Solid State Media - memory stick, flash cards
solid state hard drives
What are the advantages of magnetic media?
Fast read/write times
Huge capacity
What are the disadvantages of magnetic media
Easily damaged
What are the advantages of Optical media?
less expensive
can be read only
very portable
some can be reused
What are the disadvantages of optical media?
holds less data
slow data transfer
What are the advantages of solid state media?
last longer fast data transfer times uses less power run silently compatible with most computers large storage capacity easy to connect
What are the disadvantages of solid state media?
more expensive
size makes them easy to lose
