This morning’s Observer column.

This is a story about digital Darwinism. Once upon a time, the abiding nightmare of authors and students who used their PCs and laptops to compose books, dissertations and essays was that a random accident – theft of a laptop, perhaps, or a hard-disk crash – would be enough to vaporise years of irreplaceable work. So we all resorted to primitive schemes to protect against that terrible eventuality. In the early days, these took the form of piles of floppy disks stored at other locations; after that, we “burned” the precious files on to blank CDs; later still, we copied them on to USB sticks and flash drives that went in our pockets or on our keyrings; finally, we were even driven to emailing the damned things to ourselves.

Then along came an idea that made all these stratagems look, well, clumsy. It was called Dropbox. You logged on to the Dropbox site, registered (for free) and downloaded a small program (called a ‘client’) on to your computer. Once installed, this program created a special folder – helpfully labelled “Dropbox” – which appeared on your desktop. From then on, you saved any file that you wanted to back up in your Dropbox folder.

So far, so mundane. But even as you continued with your writing, the Dropbox client was busy in the background…