Backing up your critical files and information is an integral part of a good data management system and is the best defence against data loss due to hard drive failure or other system malfunctions. In this article we'll look at the importance of backing up your files, the various types of backups you can perform and the types of storage media available.

Data Backup

There are two main reasons to backup your files. The first is for protection in the event of a data loss incident. Over time, mechanical devices have a tendency to fail, and computers and hard drives are no exception.  Unfortunately, in many cases it comes without a warning. Backing up your files on a regular basis minimizes the effect of any hard drive or system failure.

The second reason is to store multiple versions of files that change on a regular basis so that you can go back and retrieve information from a specific period of time. Many business applications, for example, require you to go back to a previous transaction record and retrieve data from that date. Having a well organized data storage system allows you to perform this task quickly and easily.

Data Repositories

When you back up your files, you'll need to organize it in some way to make it easier to retrieve the data. There are several different models of data storage that you can use:

Full + Incremental: This data storage plan begins with a full backup of all you data. The incremental part of the backup copies every change that has been made since the full backup was made.

Reverse Delta: A reverse delta system stores the changes between current system versions and prior versions. The data repository stores all the data necessary to create a previous version of the system.

Continuous Data Protection: With continuous data protection, the system immediately saves every change that is made to your files.

Full System Backup: A full system backup allows your computer to be restored exactly as it was prior to the data loss. This includes the operating system and all other application software and data. If necessary, the full system can be reinstalled on any PC so that you could continue exactly as you left off.

Storage Media

There are several different media on which you can store your data. They each have their strengths and weaknesses.  You should choose the method that best suits your circumstances and preferences.

• External Hard Drives. These are actual hard drives that you can attach to your computer and transfer any files you need to back up. External hard drives can store large amounts of data, are reasonably portable, and can even replace your computer's internal drive in some cases. The main downside to their portability is that they can relatively easily be lost or stolen. 
• USB Flash Drives. Flash drives or data sticks are a form of external hard drive that can store data from your computer. They are typically less than four inches long and weigh an ounce or less and so are extremely portable.  They have lower storage capacity than an external hard drive and so are usually only suitable for storing relatively small amounts of data. Their small size makes them even more convenient for transport than external hard drives, but also more susceptible to being lost or stolen. One of the nice features of flash drives is that they are very durable. They can withstand a greater degree of physical abuse without losing the information they contain. 
• Online Data Storage.  Online data storage has become much more popular recently. Online storage allows you to save your information on a regular or continuous basis and store it at a remote location. This is important because data stored "off-site" is not usually susceptible to the problem caused your data loss in the first place.
• CD or DVD-RW Disks. One of the simplest and least expensive methods of backing up data files is to store them on CD or DVD-RW disks. While this is simple and convenient, the disks can only store a limited amount of data. This may be appropriate for storing data such as personal photos or files, but is impractical for backing up large amounts of data.

No matter which form of data repository or storage medium you use, the choice should be based on your current needs and circumstances. Small businesses will have different needs from personal computer users and in most cases, the amount of data you need to store will be the determining factor. Another big consideration will be ease of use. You'll want to make your backup system as simple and easy to use as possible, to ensure that you don't neglect to back up your data.