I realize I'm dating myself, but the first computer I ever owned didn't have a hard drive. It had two drive bays that held 5.25 inch floppies. Later, I bought a then revolutionary machine, an 8086 I think, with a 40 MB hard drive, and I wondered how anyone could ever fill it up. And the last time I moved, I discovered a box filled with floppies and 250 MB Zip drives.
It's obvious that none of those devices are nearly large enough to satisfy our appetite for digital music, photos, videos, presentations and the like. But there's a less obvious issue that bothers me a lot. If that old box contained a floppy or a Zip with something I needed, I'd be altogether old of luck. Where would I find a drive that would accommodate the media, particularly the cardboard-packaged 5.25 disks -- even if they hadn't deteriorated too much to be read?
You get the idea. No matter how disciplined we are about backing up our digital stuff, our efforts will be useless when the media becomes obsolete.
There is a way around this problem, fortunately, and it's storage in the cloud. Unless the data is stored in some strange proprietary format, there's no reason why it wouldn't be readable 10 or 20 years hence.
And yes, I'm going to give you the obligatory tech columnist lecture about how hard drive fail, computers get stolen or drenched with coffee and so on and so on. If you don't want out to find out one bleak day that you can no longer access the novel you've been working on for four years or pictures of that once-in-a-lifetime visit to Beijing, you'd better back up. End of lecture.
Despite my worries about the impermanence of storage modes, I'm not saying you should avoid external drives. They've gotten incredibly big and cheap, and the ones from major manufactures like Seagate and Western Digital are reliable and usually include easy-to-use backup software.
However, if you have a really major disaster such as a fire or a flood, or your surge protector (you have one, don't you?) fails during a thunderstorm, say bye-bye the next Great American Novel. Your external drive is likely used much less than the internal drive on your computer, so it will probably last a lot longer. But, it's still a hard drive, and eventually they all fail.
Less terrifying, and probably more likely, is this scenario: You're traveling and realize you absolutely, positively need a file on your backup drive, or maybe you left your notebook at home. Sure, there are ways to access a home network remotely, but most of us don't use them.
So when it comes to surviving a disaster, or just getting at something you need remotely, the cloud comes in to its own. Before I tell you about two of the most interesting cloud storage options, I'm going to give you another little lecture: Like all technologies, the cloud (and by that I mean remote, online storage on someone else's server) is fallible. Vendors go out of business, outages happen, and people simply mess up, as Sidekick users found out in October when service went down, and data disappeared for a time.
Having said that, I think the chances of a reputable cloud storage provider losing your data are a lot smaller than a failure of your hard drive or the loss of your laptop.