Sharp-eyed Earthlings will have spotted a brief gap in publication! Well, this turns out to be an interesting Earthling story that I am now going to share with you.

Before that, please note that we're back and will continue from where we left off ( we will be looking at Multimedia technology over a period of four or five columns).

So what's the story? Well, as is possible for everyone, my home computer hard-drive failed. Just like that. Working one minute, not working the next. No warning. All files lost.

But of course, as a protagonist of good backup policy, I felt totally safe, with an apparent successful backup date of three days previous to the failure. Good news ? prudent policy at work.

Unfortunately no. Earlier this year, I had invested in what I thought was an enhanced, more sophisticated backup system ? labour-saving, simple and easy to use once configured. For more sophisticated, read more complicated, at least in the first instance.

What I ended up with was a backup system that actually backed-up just the first two blocks of data in each file. Let me try and explain: Files are written in blocks of data ? chunks, if you like, that are held in the memory or on the processor and once a chunk is full, it gets written to the file ? at least that's the simple explanation. Thus, as most of the files on my hard-drive exceeded two blocks of data, my whole backup strategy since April had been rendered useless.

I was devastated, until I realised that I had a much more recent copy of my critical files on my USB-key drive. Still bad, as this hadn't been updated since July, but not nearly as devastating as a loss dating back to April.

You may ask why I should retell such an embarrassing tale of woes, particularly taking into account my Chartered IT Professional status, my 20 years experience and the obvious embarassement of it? Well, that's precisely why I should retell this story.

The key messages you should take from this are:

1"Keep it simple, stupid!" Don't overcomplicate that which need not be overcomplicated: Aiming for a simpler execution of the backup process may sound like a good idea, but unless you really investigate the complexities, copying to CD is probably as much as you need;

2 "Mix it up!" ? Don't stick with one method of backing-up key information ? back up in several modes, and put copies in several places to reduce the risk of losing data ? in my case the fact I had a copy of my critical files on my USB key saved me losing four months worth of work;

3 "Verify!" Find a way to restore the data you've backed-up to another location ? to prove your backup is of high-integrity and the data you've backed-up is complete. Don't rely on reports from your backup methodology, which report on the success of what you have requested, and not on whether you have backed-up everything successfully. If you're not sure, ask a professional to check it out for you, and ensure they don't just consult logs ? make sure they actually access your backed-up data; and

4"Always two, there are?" When you backup, make two copies of the data you're copying. On different media. Always. If it is copying to CD or DVD you use, you are even asked by the burning software whether you want to make another copy. Just say yes!

The catastrophe that befell me can befall any and all of you ? easily ? and regardless of whether the hard-drive is one day or one decade old. Whilst your manufacturer's warranty will definitely cover hardware-replacement, very few warranties cover data loss ? remember that, and how simply data loss can occur.

Next time we're back on track. We'll take a look at music first, moving to photos and video, and finally we'll pull them all together.