You can either tear out your hair when a disaster strikes your hard drive or you can prepare for it ahead of time, but data loss is as inevitable as death and taxes. An online backup service is one of the best ways to protect yourself against such threats as a crashed hard drive or accidental deletion. Natural disasters such as fires, floods, and earthquakes can also spell the end of your digital media and documents. Even if you're among the very few who diligently perform local backups at regular intervals, you could still lose data if you don't store backups offsite.
Carbonite is one of the web's most popular online backup services, and for good reason. The Carbonite client runs quietly in the background uploading your data to Carbonite's servers to make sure it's safe in case something happens to your computer. Carbonite can automatically back up documents, music, email, and other files (although it manually backs up video), and grants you access to those files and your archives on your smartphone. Carbonite supports Windows and OS X (although its Home Plus and Home Premier plans only support Windows), and make restoring your files as easy as backing them up. Your offsite files are encrypted to keep them safe from prying eyes, and all of their plans include unlimited storage for your backed up files. Carbonite's Home Plus plan extends its features and allows you to back up external hard drives and not just files on your computer, and allows you to back up full system images. The Home Premier plan includes both of those features and adds automatic backup of your video files, and a courier recovery service that delivers you backups on a hard drive to you ASAP if something terrible happens.
An online backup service isn't much use if it doesn't make the process of restoring or recovering your data quick and simple. For example, a service should offer search tools for finding particular files in your backup. It's also desirable for a service to be able to replicate an entire folder-tree structure so that it can help you recover from bigger data losses. Keep in mind that if you buy a plan that covers just one computer, you may have to transfer the account to a new PC if you ever switch your main device or if you need to restore data from a damaged computer to a replacement.