Backing up and archiving data
dataValues, typically letters or numbers. needs to be backed up for many reasons:
- a user may delete an important file
- hard disk driveA device used to store large amounts of data. can fail
- a virusA small program written to cause harm to a computer. can wipe out data
- a fire may destroy the building where the data was being stored (businesses will often store their backupA copy of important files that is kept separately in case the original files are lost or damaged. off-site)
If the data wasn鈥檛 backed up then the consequences could be disastrous depending on what data was lost. If a business lost details of all the payments it had yet to receive the business could go bankrupt as they wouldn鈥檛 know what was owed to them or by who.
Your average home user may not backup their data but those who do will most likely use an external hard disk.
Frequency of backups
Some data is more valuable than other data and some data is changed more frequently than other data. These are the kind of issues that must be taken into account when deciding how often to backup data.
The value of the data should determine how frequently it is backed up.
If the data doesn鈥檛 change often then it doesn鈥檛 need to be backed up as often, maybe just after each change. If the data changes frequently then it should be backed up frequently (maybe every evening).
Archiving
Some data may not be being used very often but it may still be useful or needed in the future. In this case data can be archived. Archived data is copied to a suitable storage medium (perhaps DVDA plastic, circular disc used to store music, video or data. DVDs are optical storage media, similar to CDs and Blu-ray discs. or magnetic tape) then it is stored safely and securely. The original data is then deleted from the computer system. This is done to free up storage space for new data.