Please enable JavaScript.
Coggle requires JavaScript to display documents.
STORAGE DEVICES AND MEDIA (3.2 (this section briefly describes the two…
STORAGE DEVICES AND MEDIA
3.1
Backing up of data
Secondary storage and compares the advantage&disadvantage of each type,
3.1.1
What is backing up of data?
Backing up refers to the copying of files to a different medium in case of a problem with the main secondary storage device.
3.1.2
Why back up data?
safeguard against loss of data due to the failure of the original secondary storage devices
safeguard against damage caused hackers .
Backups made in case the files need to be used elsewhere
Backups don't necessarily guardt the effect of a virus .
Serial access**
3.2.1**
When using serial access it is necessary to start at the beginning of the file and then access each record in turn until the required record is found
3.3
Secondary storage data
Byte is used to measure the size of a memory or a storage
storage
sizes or files sizes are measured in kilobytes ,megabytes,gigabytes,and terabytes
3.2
this section briefly describes the two main methods of accessing data the three new important tern is field,record,file
record
for car
Stored in an allocated space known as
field
putting all the data together is called a
file
3.2.2
Direct access is used with magnetic disk,optical media and social state media