One thing about the internet is that it is always changing. It is continually in flux, it is changing our world, it is changing how we do business, it is changing how we manage our relationships and live our lives. But it is not the 'internet' acting in isolation, it is the internet providing a medium for expression, a mechanism for communication and the machinery to do business. Exhortations abound that this is now "Web 2.0".

So when we thought about the expression "Web 2.0", we asked ourselves whether this was something different than before and if it was, what were we likely to see following in its footsteps? Our initial research only caused more confusion, so we conducted a brief but very unscientific straw poll. Here we have tried to summarize the general consensus of contributors' comments along with other background materials.

There seem to be several different levels to address this question. First, we might look at the physical nature of the internet, the underlying technology, to see if there have been some radical shifts, some new inventions or extensions that would let us define a change from the "original" web ("Web 1.0") to a new form. We haven't found any real substantiation of this. Tim Berners-Lee (inventor of the world-wide web) is actually often quoted as saying that technology components of "Web 2.0" have existed since the early days of the Web (1991).

So we took another look at the software or types of applications that are now deployed on the web or are accessible over the internet. Before there were the standards of the World Wide Web, the internet was accessible through relatively arcane commands. Certainly, a good graphical interface represented by modern day browsers wasn't available. The introduction of these graphical browsers, with (hypertext) links, made one of the first step changes in the use of the internet. Initially, browsers accessed published information that was nearly all textual. Gradually, as local computing power grew, graphical material was added. Design issues from publishing and usability issues from systems design became more important concerns for publishers trying to reach and communicate with their audience.

As developers built and found programming tools to work with web pages, the nature of applications shifted to be much more interactive. Computing power was unleashed for almost any purpose one could think of. Instead of delivering static web pages, users began to interact with the content. Some traditional application development moved to the web environment delivering computing power for such applications as reservation systems, shopping and purchasing. The content was delivered and controlled by the publishers and their software; the users behaved like conventional consumers. Web based "eCommerce" became a reality.

Some publishers realized that it would be prohibitively expensive to build their target applications alone. Enter the wiki model introduced by Ward Cunningham (1995) and adopted by Jimmy Wales and friends for Wikipedia, a collaboratively built encyclopedia, which we refer to often. Now it was possible for visitors to a web site to edit and contribute the very content of a publisher's database. As content editing tools improved, especially for graphics, audio and video materials, this introduced novel applications such as YouTube, mySpace and Facebook to name just a few. This is largely where we are today.

So from an application standpoint, we might say that once Tim Berners-Lee had created the World Wide Web we had "Web 1.0". Once applications allowed web sites to became interactive for visitors, for whatever purpose, we can call them "Web 2.0". The more interactive, the more they are "Web 2.0". This seems to us to reflect the biggest shift that might justify usage of the terms.

What could possibly follow that we might call "Web 3.0"? A little crystal ball gazing might tell us that predictions rarely come true. But there is one aspect of the way information is published on the web that intrigues us. Instead of deliberate 'man-made' authoring of information as manifested in both Web 1.0 and Web 2.0, we can see semi-automatic or automatic gathering of information for web-publishing taking the human out of the loop. There is already a huge array of data gathering devices: satellite imagery, surveillance cameras and so on. Turning their data into useful, publishable information is a productivity issue. It is expensive to have humans interpret these data streams for publishing purposes, how can we do it automatically? One application that springs to mind that may already be in development, is automated traffic and weather reporting that delivers concise information and even advice to drivers on their onboard, web-enabled, navigation screens. Reducing the traffic 'load' on a constricted freeway 10-20 miles away is a real practical benefit, especially during say hurricane evacuations.

But just taking an application view is socially and culturally sterile. How people are using the power of interactivity may have the biggest consequences than its existence. Migrating businesses from bricks and mortar to the virtual, eCommerce world of the internet has had huge implications. Allowing communities of people who interact remotely in their own distributed and perhaps self-defined 'tribe' has social, political and economic implications. For some this is already here and for them makes "Web 2.0" something different in the world.

But there is another tune beginning to be played on the theme of "Web 2.0". It's a type of application that is more a cultural phenomenon than a functional one. It is driven by purpose rather than design and allows a deeper control of content by consumers in an environment provided by publishers. Enter Second Life and to some extent the social networking services. When the computing environment begins to change under the influence of users something new may be afoot. Enabling this trend may be the appearance of software agents that run independently and are capable of alerting their owners to changes in their environment, changes stemming from interactions with other agents or from other users, or from sources of information from the broadening use of sensors. We think this is the genesis of the next level, perhaps justifying the term "Web 3.0".

Generally, our straw poll agreed that there is no clear cut definition for "Web 2.0" or any of its precursors or successors. It is seen as much of a catch-phrase, but what it is believed to be varies enormously with people's perspectives. So in an effort to embrace an Occam's Razor, try this simple matrix:

where we hesitate though to define 'control', 'content' and 'environment'.

Finally some quotations for food for thought:

"With Web 1.0 no-one knows you're a dog. With Web 2.0 someone knows your a dog and will tell everyone else." - contributor

"Web 2.0 communities have paved the way for new startups offering alternatives to technology incumbents, such as Microsoft and IBM. Traditional businesses must embrace these new models or risk losing market share." - eWeek magazine.

"A Web 2.0 application is any Internet application whose value intrinsically grows with the amount of its users." - blogger

First published in EmTechNews Vol. 4 No. 3, October 2007.