Kategóriák: Minden - cost - access - devices - media

a Carol Robertson 14 éve

290

Backing Storage

Various types of backing storage are available, each suited for different purposes based on capacity, speed, and cost. Optical disks like DVDs and CDs offer varying capacities and are differentiated by their ability to be rewritten or not.

Backing Storage

Backing Storage

Solid State

USB flash drive
Used as portable storage
Capacity up to 64 Gb
Memory Card
Cost up to £100 depending on capacity
Used for portable devices eg. digital camera
Capacity up to 16 Gb
Fast to read and write to

Optical Disks

DVD - digital versatile disk
Capacity normally 4.7 Gb but up to 17 Gb
DVD-R
DVD-ROM
DVD-RW
CD - compact disk
Capacity up to 700 Megabytes
CD-ROM

Cannot be written to

CD-R

Can be written to once only

CD-RW

Can be written to again and again

Fast to read

Magnetic Tape

Cost up to £150 depending on capacity
Used for BACKUP (copies of files)
Slow to read and write to
Sequential Access
Magnetic Media

Floppy Disk

Cost approx 15p each
Portable
Small capcity
up to 1.44 Megabyte
Slow to access and write to

Hard Disk

Cost up to £200 depending on capacity
Can buy portable hard disks
Used for continuous, interactive access
Very large capacity
Up to 1 Terabyte
Very fast to read and write to
Random Access
Magnetic media