Do I need to back up files that are already in cloud storage?

Where's the Cloud?

Even if you haven't been consciously using a cloud storage service, you probably have data stored in the cloud. With many services, you post something or send an e-mail and don't even think about storage. If you use Hotmail, Yahoo or another web-based program, your e-mail history is in the cloud. If you post pictures on Facebook or another social networking site, those images are in the cloud. If you work with others through Google Docs, those documents are in the cloud. If you've posted a video to YouTube, it's in the cloud. If you pay GoDaddy, or a similar company to host your blog, all your blog entries are in the cloud.

We call it the "cloud" because for years, computer professionals have used a cloud icon as shorthand for everything that makes the Internet work – servers, data centers, networks, storage, various services. The cloud is made up of shared resources for us to access through our Internet devices, and we use it on a self-serve basis.

In recent years, as more businesses and individuals see storage as a problem, scores of businesses have sprung up offering to keep data in the cloud for a fee. Some offer a limited amount of storage free, in hopes of gaining your business when you want more.

Essentially, all you need to store data in the cloud is an Internet connection and an arrangement with someone with a server.

You'll want to know more than that about the storage you choose, though. Most cloud systems back up the data they store in multiple computers in multiple locations. That way, if a catastrophe strikes in one place, data is protected elsewhere. Storing data in multiple places is called redundancy. Backing up the data you already store in the cloud would add another layer of redundancy that may not be worth the trouble.

Let's look at the pros and cons of cloud storage. Read on to the next section.