Backing Storage

Plus de détails

7C-IT

par School Admin

i-Sparks Tobacco - VISION

par Thomas Juli

Maintenance

par Wasana Wickramasinghe

Portable Devices

par David Belcar

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