In August of 2016, Delta Airlines had to cancel more than 1,300 flights, at a cost of $100 million, not because of weather or mechanical problems, but because the company's computer systems went down. If it can happen to a big corporation like Delta, don't think it can't happen to you. All technology, whether it's a brand new iMac, a spaceship, a hover board, a Web mail service, or a ten-year-old PC running Windows Vista, can potentially take a sudden nosedive. Hard drives are notorious for crashing, and ransomware can make a computer's contents inaccessible. Sometimes it's not even a fault of the technology: Fires, flooding, and other natural disasters can render PCs and other tech hardware inoperable. And laptops get stolen. You need insurance. With digital content becoming paramount for not only business assets—documents, plans, financial spreadsheets—but also for personal assets such as family photos, videos, and music, protecting with backup software is more important than ever.
Both Windows and Mac OS X have beefed up their built-in backup tools in recent years. Windows 10 includes a File History feature and a full disk backup feature, and OS X includes its Time Machine software. Both of these are well worth running, but they both have some limitations, lacking some of the extra benefits you get from running standalone backup software.
How Backup Software Works
The concept behind backup software is pretty simple: Make a copy of your files on storage separate from your main hard drive. That storage can be another drive, an external drive, a NAS, a rewritable disc, or an online storage and syncing service. Should you lose the files, either through disaster or simply by deleting them or overwriting them, you can just restore them from the saved copies.
But in order for this to work, the copies of your files must be updated regularly. Most backup software lets you schedule scans of your hard drive for new and changed files daily, weekly, or monthly, but my preferred option is to have the software continually (or at least, say, every 15 minutes) monitor your drive for changed or new files. Several products here offer this continuous backup option.
More granular options include whether backups are full, incremental, or differential. The first is pretty obvious—all the data you've selected for backup is copied in its entirety. Incremental backup saves system resources by only backing up changes in files from the last incremental backup, and differential backup saves all changes from the last full backup. With incremental, you need the latest full backup and all the intermediary backup data to restore a file to its original state, whereas with differential, you just need the last set of differential backup data and the first full one.
A couple of security options are usually available when setting up your backup: password protection and encryption. Using both of these is a good idea if the data you're backing up is at all sensitive. Another option offered by many backup applications is versioning. This lets you specify how many previous versions of your files you want to preserve, and for how long. I recommend maxing this out, especially when you're storing backups locally, with no annual fee for hosted online backup. In any case, the incremental changes don't eat up a ton of space.
A step further than the simple copying of files is copying the entire hard drive, including system files, as what's called a disk image. This contains every bit of data on the drive and offers stronger protection, since it enables you to recreate a system after a hard drive failure. Some products can even update a disk image nearly continuously. But that extra protection comes at the price of more complexity in setting up and restoring. Usually you'll need to run a pre-boot environment from startup media to restore a system image, since doing so from within your main OS isn't possible.
For another—highly recommended—approach to backup, consider online backup, also known as cloud backup. Services like IDrive and SOS Online Backup securely send your data over the Internet and save it on remote file servers in encrypted form. The big plus of this option is that the data is off your premises, and therefore not susceptible to local disasters. The downside is that they tie you to annual fees, and uploading and downloading backups is slower than loading local copies. Some online backup services, such as CrashPlan and SOS Online Backup, include software for making local backups, as well.
Restoring From Backup
How you set up your backup affects how you can restore it. If you've backed up your entire disk image, you'll need to start the system from bootable media such as a DVD or USB stick that you created in the software. (You should definitely create one of these types of rescue media if your software offers it.) You also may need to attach another external drive containing the backup data along with the boot media. Several of the programs included here even let you restore data from one PC to another that has different hardware. This is useful when you simply want to migrate to new PC hardware, as opposed to recovering from a disaster.
For restoring individual files, several of the applications, such as Acronis True Image and Paragon Backup & Recovery, give you the option of choosing among previous versions of the files you've saved. Which file versions are available to restore depends on how frequently you've run backups. This is why the continuous backup option mentioned above is preferable. With that option, ideally, every time you save a file, it's backed up and you can get back to any previous point in time.
If all or some of this has sounded like a foreign language to you, you should definitely check out PCMag's Beginner's Guide to PC Backup, which offers help and detailed information on the different kinds of backup available to you. The article makes recommendations on what you should back up and what media you should back it up to.
Below are links to our latest local backup software reviews. Have you got a story about an occasion when backup software saved your bacon or an opinion about one of the applications we've reviewed here? Let us know in the comments below.