Data or access to data stored on a personal computer, phone or tablet can be lost, often without any warning. Hardware failure, theft, or malware infection (such as the cryptolocker ransomware attack) can make recovering your data expensive or impossible. You need to back-up your data.

There are two main options for backing-up your data:

  • performing your own back-ups to a storage device (USB or external hard drive)
  • backing up to an online (cloud) service.

Comparison of back-up options

Storage device Online back-up
Some initial outlay No initial outlay
No ongoing cost Monthly cost
Mainly suitable for personal computers Suits all devices
Does not require/use an internet connection Requires an internet connection and may impact your monthly data allowance
Can be easily and securely stored off-site Provides an inherent off-site back-up
Generally more 'manual' Generally more automated
As requirements increase, you may need to upgrade your storage devices Will scale with requirements (although cost will also scale)
You manage the security of the storage device yourself Security is managed by the back-up service, which may be hosted overseas and subject to different privacy laws

Back-up applications

Back-up applications are available that can partially or wholly automate this process and can also perform full back-ups. These applications come with some operating systems (for example Windows Back-up or Mac OS) may be bundled with storage devices, or may be purchased separately.

Different applications have differing functionality. Consider the information below and look at online reviews before selecting a back-up product to suit your needs.

Offsite back-ups

If your house or business is burgled or burns down, the back-up storage device may be lost with your personal computer, so offsite back-up is critical.

  • Store a back-up device at another physical location.
  • Use online back-up where your data is stored in a datacentre with a high level of physical security.

Frequency and types of back-ups—advantages and disadvantages

Back-up type Advantages Disadvantages
Full back-up
  • backs up all the data on your computer including the operating system and applications
  • complete restoration of the computer is possible.
  • needs a large storage capacity
  • takes a lot of time to complete.
Partial back-up
  • saves only folders and files you request
  • needs far less capacity
  • doesn't take long to complete.
  • doesn't provide full disaster recovery.
Incremental back-up
  • performed following a full back-up
  • backs up only the files that have changed since the previous back-up.
  • provides full recovery
  • needs much less storage capacity and time.
  • incremental back-ups can require careful management, however many applications manage this automatically.

The benefit of multiple back-ups

While maintaining one back-up provides protection against sudden incidents, such as the theft or failure of a computer, greater protection can be gained by having multiple back-ups covering different periods, for example one week ago, one month ago and six months ago. 

The limitation of only having one back-up is that sometimes data loss can happen slowly in the background and may not be noticed until too late. Some types of ransomware and hardware faults can cause this, and sometimes users inadvertently delete important files without realising it. The loss of an important file may not be noticed for a while, by which time the most recently backed-up copy will have been overwritten and lost.

While keeping multiple back-ups can require more management, time and capacity, they allow you to 'go back in time' much further to retrieve important files.

While a partial back-up cannot provide full disaster recovery, it can be used in conjunction with the original operating system and application disks to restore basic system functionality. While this may return access to personal files, this process can be time consuming and may not restore the system completely to its pre-disaster state.

Disaster recovery and back-ups

Using a back-up to recover from a disaster, such as the theft of a computer or catastrophic hardware failure, can be complicated. Use of the back-up to restore your (replaced or repaired) computer to its pre-disaster state may require specialised technical services.

Performing a full recovery generally requires the existence of or ability to create "boot disks" capable of accessing the back-up files, or use of a second computer to copy the backed up content to the repaired/replaced computer.

If the new computer is significantly different from the one that was backed up, complete restoration may not be possible. However, even when complete restoration is impossible, individual files should still be able to be restored from the back-up.

Develop a back-up strategy

  • Develop a disaster recovery plan. Start by assessing your level of risk and identifying what actions you can take to minimise the risk.
  • Assess what data and programs on your computer need to be backed up and how often. You may either back-up all the data and certain programs on your hard drive each time you back-up, or you may choose to do incremental back-ups.
  • Incremental back-ups only include the files that have changed since the last back-up therefore saving time and space.
  • Select a back-up device that is large enough to store the files and fast enough, so it is not too time consuming. Examples include CDs, DVDs, memory sticks or an external hard drive.
  • Make a note somewhere obvious, such as in an office diary, reminding you to do the back-up.
  • Regularly test that your back-up process is working.
  • Store the back-up copies in a safe location away from your computer systems, such as away from your home or business premises. Remember putting this information on portable media makes it vulnerable to physical removal so secure it.
  • Do not use the same computer or network to store your back-ups. If you system is compromised you may lose or be unable to access the files.

Where to get help

Issue Contact
You are experiencing technical difficulties with your computer
  • your local computer repairer
  • your local computer retailer.
You are experiencing difficulties connecting to the internet Your internet service provider.
You are looking for more information on backing-up your desktop or laptop computer
  • your device manufacturer's website
  • Whirlpool or other discussion forums.
Information on recent threats Sign up to the free Stay Smart Online Alert Service.

A full list of useful contacts can be found on the Contact us page.

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