In general, when we speak about cloud backup files are mirrored from a device to the cloud. This can be your computer, a server, your mobile or any machine that stores data locally. Using the cloud reduces the risk of total data loss because data is stored remotely. Whatever happens to your computer you can always retrieve your files because of that 'mirroring process' that took place earlier via the internet.
Bitcasa Infinite Drive is relatively new, but it's one of your favorite cloud storage providers in general, mostly because they offer virtually unlimited stroage for syncing and backups. When we say unlimited, we mean it—some of you are using terabytes of storage with Bitcasa. It's not primarily a backup service though, and while it was built for file syncing and storage, the Bitcasa desktop client does support regular file backups. Bitcasa supports Windows and OS X, and encrypts all of your files before uploading so they stay safe from prying eyes. Bitcasa even keeps revision history, so if you've backed up a file multiple times and need an older version, you can pick it out and restore it. Plus, you can use the Bitcasa mobile apps for iOS, Android, and Windows Phone to access your data on the go.