Zusammenfassung der Ressource
1.3 storage
- Keywords
- secondary storage
- optical
- magnetic
- solid state
- durabiltly
- reliability
- portability
- capacity
- speed
- Storage
- characteristic
- estimate
- overheads
- secondary storage
- long term storage of data, files and information
- we need to store this so we can access it later and to use it later
- we need secondary storage so programs wont reinstall every time we use it
- when a device is not constantly connect connected to a computer
- They are needed to back up data and for
larger storage capacity
- Advamtages
- Memory is non-volitale
- Data is not lost
- Types of storage
- Optical
- a laser light creates mark in a pattern on the disk
- advantages of optical
- cost
- portability
- durability
- capacity
- Most suitable for distributing a movie
- storage device for distributing for a movie is a DVD
- Magnetic
- read/write move across the medium and change how
magnetised that part of the medium is
- Advantages of magnetic
- capacity
- speed
- portability
- reliability
- cost
- Solid State
- Made of microchips
- The state of the switches determine
if a 1, or 0 is stored
- Advantages of solid state
- Portable
- Durable
- Fairly reliable
- Characteristics of storage devices
- Capacity
- how much data will it
store
- speed
- how fast can the data be
accessed
- Portability
- how easy is it to move it from
one place to another
- Durability
- how well does it last e.g if it
was to be dropped
- Reliability
- how consistently does it perform
- Cost
- How much does it cost
per KB, MB or GB
- CD-ROM
- Suitable for distributing music
- Can be read by other devices
- is read only, cant be over written
- cheap to produce
- Magnetic tape
- Slow to write and read
- all the data has to be read before the
data you want