What is it that compels people to publish their life online?

Blogs, Moblogs, Photoblogs, Vlogs, iCalendar, iTunesBlogger, flickr, del.icio.us, geourl. Social bookmarking, social networking, aggregating and subscription. What is it that drives people to publish their life online? And what is it that compels them to read about others’ lives?

One explanation might be that people seek to present an idealised avatar of themselves, a “virtual me” that can be published free of the flaws and foibles of the physical version. Another explanation is that they merely seek to intersect with others in dimensions that are harder to express in meatspace - who else in the world like this strange band? Who else is going to this concert? Who has a male cat of the same breed as my fertile female cat? And what sort of a person are they?

It is overly simplistic to think of the web as a glorified pick-up joint. The urge to express oneself runs deeper than that.

I like to think of the new, highly-linked web as adding additional dimensions to our navigation through the world. We already have a simplistic version with the telephone book and telephone. The semantic web (which is what we’re talking about) will revolutionise the world in a directly analogous way, as you shall see.

When you want to talk to a friend on the phone, you know their name and possibly where they live. So you pick up the telephone book and look them up by name, suburb and possibly street. This provides you with a number, which you then punch into the telephone to call them. If they’re home, they pick up. If they’re not, you can leave a message (assuming they have an answering service).

What you have done is a single, one-way index lookup and then transcribed that information into a tool that allows you to perform the desired task. You are restricted to looking up the information in a single dimension, and once it has been looked up it has only one use. It’s a massive advantage over pre-telephone days because you can transcend space to contact the person you are after, albeit in a fairly restrictive way.

Now imagine if you could look them up by interest, location, or age. Suddenly, you can look up more than just people - you can find images, movies, articles, books. You can search by almost any attribute - physical location, date, time, degree of trust, rankings by your friends. Imagine if you could look up photos from a single location throughout recorded history, as though you had a time-travelling camera. Such things are possible - now - with the semantic web.

Now, people have been babbling on about this for years, particularly the boring and bureaucratic XML consortium, and people have typically said “Huh? That sounds like a fancy specification but what the Hell does it mean for me, sitting here in traffic in the stinking heat, wondering whether the desire to kill myself will pass by lunchtime?”. Actually, that’s not true. Typically people have ignored them.

Here’s what I think. I am assuming here that you want to know. Possibly a little presumptuous on my part.

I think that all this extra metadata - information about information, such as the coordinates at which a photo was taken - is slowly but surely entangling the online world with the real world. Dozens of books have fantasised about launching ourselves into “cyberspace”, flying through fanciful virtual worlds populated by people with supernatural powers. What is actually happening, which is even more exciting, is that the virtual world is leaping through that barrier the other way. Tendrils of the vast information universe that we’ve built online are extending into our world - your iPod carries around your “virtual” music as invisible files, as well as your contact and calendar information. If I make an appointment on my phone, my Apple Powerbook makes sure it appears on my website - invisibly. Calendars that people have built on the other side of the world can cause my mobile phone to beep and remind me that the new Tim Burton movie is about to be released. And all this is happening now.

Soon it will be possible, through the power of GPS and widespread (and cheap) wireless internet, so tag real objects in the real world with arbitrary digital information. You’re in a restaurant. You decide you like the food, so you push a couple of buttons on your phone which publishes a star-rating of the restaurant online, on your web presence, tagged with the GPS location. You don’t need to enter the name or address because that information is already associated with that lat/long location (provided by your phone) in Google. You don’t need to enter the time and date because your phone knows it. You don’t even need to indicate that you’re in a restaurant.

These star ratings could be like a heat-seeker. Hold up your phone and just ask it where in the surrounding blocks you’re likely to have the best time.

Of course, everyone’s different and you shouldn’t just trust some stranger’s opinion. That’s where trust networks come in. Over time, you develop a trusting relationship with your friends, and they with their friends, and so on. This provides some weightings for the informational tree that allow you to balance the information in favour of those whose opinions you respect, enhancing the quality of information you receive about your environment.

The question is: How do we make this invisible? How do we leverage the power of existing information and integrate it at every stage to make the whole process as seamless as just knowing what you need to know while barely needing to think about it?