In the real world we own our name. I've got a birth certificate somewhere which confirms who I am and, short of changing it by deed poll, this name will remain with me until I shuffle off this mortal coil. Although there's quite a few Gary Gales out there on the Internet, this one is inextricably me and no-one can take that away from me.

But in the online world we don't so much as own our names, we ... lease them. I've "owned" the vicchi.org domain name continuously since April 2001 but it's not ownership as we understand it in the real world. If I don't renew my domain every so often it'll lapse and someone else, should they wish to, can take it over. This is an arrangement I can live with as it's the way the Internet domain name system works, like it or hate it. I will, at least, get some warning to renew my claim on (temporary) ownership of the domain as there's a financial arrangement at play. I pay some money and, domain grabs notwithstanding, I keep the domain for the duration of the period I've paid for.

One of the things I write about a lot on this blog are the areas of location and online, or digital, identity and how these two areas overlap and sometimes conflict.

I write about this stuff not only because I'm lucky enough to work in both of these areas but I also find them fascinating, compelling and nowhere is this more evident in how individuals and organisations views this arena.

Companies, if they're foresighted enough, are making major plays in the location field, fuelled by the proliferation of location aware devices (cameras, phones, netbooks and the like) and by the convergence of these devices (I use an iPhone ... is it a phone, a camera, a GPS unit, an internet terminal, a computer or some combination of them all?). There's much value to a company in knowing your customer's location and how it changes over time. Indeed it's a truism that it's much less about where you are now and much more about where you've been.

Individuals, if they're informed enough, know about the plays the companies are making in the location field and  should know how to determine the value proposition that is offered when they give up their location.

A couple of weeks ago I wrote an article on this blog that highlighted the issues around managing our digital identity.

"Managing our digital identity through those sources we know about is a challenge for a significant percentage of the online population"

Then this morning, (ex Yahoo!) Cathy Ma posted a link to her recent blog post about the Personas project being run by Aaron Zinman at MIT. Personas tries to "show you how the internet sees you". So I duly surfed over to https://personas.media.mit.edu/ and plugged in my full name and some time later a rather slick Flash animation gave me this supposed "characterization of the person".

"I'm just a face in the crowd, Nothing to worry about, Not even tryin' to stand out, And I have nothing to say, It's all been taken away, I just behave and obey"

Trent Reznor, Nine Inch Nails, Getting Smaller

Ten years ago our online identity, if we had one at all, was a simple affair to manage, comprising of an email address and perhaps an avatar name or two. Fast forward to the close of the first decade of the 21st century and it's an altogether more complex affair. You've probably got several email addresses, possibly some domain names and then there's the plethora of social networking sites that you frequent, Twitter, Facebook, LinkedIn, Bebo, MySpace and so on. All of which define the online version of "you" in much the same way as your passport, driving licence and bank account defines the offline "you".

The key difference is that the online version of "you" is much more subtle, complex and diffuse. We leave scraps of our path through the internet behind us. At the Being Digital conference in London earlier this year, I tried to explain this with the clumsy phrase "digital dandruff"; in the soon to be published book, "My Digital Footprint", Tony Fish far more elegiacally describes it as our digital footprint, which is "the digital 'cookie crumbs' that we all leave when we use the some form of digital service, application, appliance, object or device, or in some cases as we pass through or by".

Managing our digital identity through those sources we know about is a challenge for a significant percentage of the online population. But despite being a challenge, it's one which is achieveable if you're willing to put enough time and effort into it. But most of us don't have the time or are unwilling to put in the effort, so our digital cookie crumbs and the varying online versions of "us" stay online, ready for someone with the time and effort to search for, find and put together with profit in mind.

Some people take an active role in managing their digital footprint and try to exploit it. Some people also try to exploit other people's digital footprint. Let's look at a concrete example of this.