Install it and then go to your main file storage folders to select files and folders to back up (right-click in Windows, or use either the Carbonite Preferences utility or Ctrl+Click in Mac OS X 10.5 or higher). You can limit Carbonite's Internet system impact by dialing down its processor usage, but that's up to you. At the default settings, we've never found or noticed any appreciable system slowdown or effect. We've also found that Carbonite's default backup settings work for almost everyone, but you should use the Windows File Explorer or Carbonite Preferences in Mac OS X to add whatever the default settings have missed, or deselect things that are not in need of backup. You'll also note that Carbonite by default does not back up Windows or Mac system files or folders. The reason is that restoring an old system backup to a computer that has been hardware modified or otherwise altered since the last system files backup can actually mess up the computer to the point of unusability.
Be clear about one important thing. Carbonite is an online backup service - and a very good one. But it is not a permanent, archival file storage service. Where Carbonite is concerned, online backup and online storage are two things are different for one notable reason: If you delete a file or folder of files from a hard drive being backed up by Carbonite, after thirty (30) days, that file or folder of files will be deleted from your Carbonite online backup as well. Don't forget that, and life with Carbonite will be very good indeed.
All that means Carbonite online back up is great, but it's not quite a one-stop online solution. Consider subscribing to a Carbonite HomePlus account or higher, because you get something called Mirror in the deal. Mirror does a complete drive backup to a local, external hard drive, and the backup is archival. It makes for a very complete, secure, backup plan.
I've been a unswerving Carbonite user since 2006, the year after the company started in business. It has been an interesting and satisfying ride. In 2010, a boot drive crash on my main home-office PC combined with a failure of the same system's internal local backup drive had me dithering in anger until my wife reminded me that everything was backed up by Carbonite. I had been using the utility for so long without having to resort to it for file retrieval, that I had forgotten it was even around. After replacing the somewhat aged, dead PC, restoring all of my files - and I do mean all of them, including a file I'd been working on only a few hours before the catastrophic drive failures - was a matter of a few hours of downloading. The only things that have changed in my backup security since 2010 are that I now have a Drobo unit running specifically for digital image and digital video files (a secondary backup), and I'm using Carbonite HomePremier instead of the basic Home version. As for Carbonite's value? It's priceless. Set it and forget it. A single Carbonite license can be installed on any number of computers because charges are for data backup, not individual computers. Carbonite pricing is extremely competitive and it's a superb value.
Cons: Check carefully which version you're buying. It's explained clearly enough on the Carbonite site, but note that while Carbonite Home is available to Mac OS X users, Carbonite HomePlus and HomePremier are not - the last two are Windows-only for now. Both of the current business versions are available for Windows XP or later and Mac OS X 10.5 or later.
Pros: Carbonite saved me once. It has saved several of my staff more recently. If you currently have a back up system that is leaving questions in your mind, you need to resolve the matter by putting in place something which is automated and very easy to manage. School, college and university studies and research (laptops, laptops, laptops and more laptops), and home-office management and small business management are tough enough without also having to agonize over complicated data backup 'strategies' which are sometimes not there when you need them. Carbonite just works. You can get into somewhat greater depth by using Carbonite Mirror for local backup of entire systems too, which is not necessarily a bad idea either. Carbonite has evolved into a very complete and robust service that is standing the test of time. The data you save may be your own, but more important, the data you can get back quickly after a drive failure or a local backup failure, will be the data and files you need right now. Carbonite works exactly as its makers say it's supposed to work. No surprises. We've got lots of file backup software purchase links on this page, but Carbonite itself is sold only through the company's web site. Highly recommended.