To sum it up, what exactly is this “cloud computing”?

Question by Kaitlyn: To sum it up, what exactly is this “cloud computing”?
What do people mean when they talk about “cloud computing” in magazines, advertisement, commercial, companies, etc?

Or is my question too broad?
***Also, why is there so much investment going into it?***

Best answer:

Answer by Hugh
The “Cloud” is basically a remote computer that allows you to upload and save your files. It can act as a backup or facilitate collaboration.
Google Docs and MS Sky Drive are good, free examples.

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