This old dog (devil-dog) missed this trick: What's a "cloud"?
Cloud computing basically just means that the data is stored on a computer out on the internet rather than on your local computer.
Gmail is a good example of a cloud-based email provider. Doesn't matter which computer you sit down to - you log into Gmail and your email is also there.
Google also does similar functionality such as Google Docs, which is a word processor and spreadsheet program that runs in your browser. The files you save are stored on Google's servers, so no matter what computer you're on you always have access to your files.
They also have similar cloud based products for music, bookmarks, photo libraries, etc.
Some businesses even take it a step further outside of the application layer with things like Amazon's EC2 Cloud Computing technology. Basically you can store an entire "virtual" computer system in the cloud. It can be booted, you can remotely login to it, and it does all the same work that a local computer would, but its actually running on Amazon's servers.
Its a great way to minimize the risk of local damage taking out a system. The big cloud providers like Google and Amazon have replication and such running so that if one of their data centers was destroyed the cloud functionality automatically fails over to another facility.
Very good stuff from an IT perspective
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