Data loss

Data loss is an error condition in information systems in which information is destroyed by failures or neglect in storage, transmission, or processing. Information systems implement backup and disaster recovery equipment and processes to prevent data loss or restore lost data.

Data loss is distinguished from data unavailability, which may arise from a network outage. Although the two have substantially similar consequences for users, data unavailability is temporary, while data loss may be permanent. Data loss is also distinct from data breach, an incident where data falls into the wrong hands, although the term data loss has been used in those incidents.

Studies show hardware failure and human error are the two most common causes of data loss, accounting for roughly three quarters of all incidents. Another cause of data loss is a natural disaster, which is a greater risk dependant on where the hardware is located. While the probability of data loss due to natural disaster is small, the only way to prepare for such an event is to store backup data in a separate physical location. As such, the best backup plans always include at least one copy being stored off-site.

The cost of a data loss event is directly related to the value of the data and the length of time that it is unavailable yet needed. For an enterprise in particular, the definition of cost extends beyond the financial and can also include time. Consider:

The frequency of data loss and the impact can be greatly mitigated by taking proper precautions, those of which necessary can vary depending on the type of data loss. For example, multiple power circuits with battery backup and a generator only protect against power failures, though using an Uninterruptable Power Supply can protect your drive against sudden power spikes. Similarly, using a journaling file system and RAID storage only protect against certain types of software and hardware failure. For hard disk drives, which are a physical storage medium, ensuring minimal vibration and movement will help protect against damaging the components internally, as can maintaining a suitable drive temperature.

...
Wikipedia