The Web rests for no one.

The year started with people still trying to consistently define "Web 2.0," which describes an increasingly social online experience combined with programmable Web sites. It ended with people wondering what Web 3.0 will be.

Web search giant Google solidified its spot as the Web 2.0 "sugar daddy" in 2006, with its acquisitions acting as a barometer for what's hot among Web start-ups.

It shelled out $1.65 billion in stock for video-sharing site YouTube, a company not even two years old. It also bought the tiny company that created the Writely online word processor, as well as the wiki platform company JotSpot.

The purchase price of YouTube--and rumors of other corporate buyouts of popular sites like Digg--helped fuel a discussion of whether there is an investment bubble in the Web.

Bubble or not, Web start-up activity, particularly among very small companies, is on the rise as entrepreneurs experiment with online businesses around social software and media. TechCrunch, for example, emerged as a must-read online blog for Web 2.0 investors and entrepreneurs as well as a new type of media company.

Web 2.0-related conferences generated news. The first Office 2.0 Conference was held, showing the growing viability of Web-based productivity applications, which some people view as potential replacements for Microsoft Office.

The organizers Wikipedia hosted Wikimania, where Jimmy Wales, the co-founder of the online encyclopedia, urged contributors to focus on the quality of entries.

MashupCamp was one of several "unconferences," which are semi-organized meetings. This one brought together developers to discuss emerging mashups, which are applications that automatically pull information from various Web sites to create something new.

Not to be left out, Microsoft organized its first Mix conference for Web developers and Web designers, where company chairman Bill Gates urged developers to build "user centric, not device-centric" applications that combine Windows and the Web.

Meanwhile, technologies and ideas associated with Web 2.0 built a beachhead in the corporate world.

Rather than sell to corporate IT customers, Google and on-demand software companies are looking to get into businesses through the back door. Such a move starts with an individual using a Web-based product at home, liking it, and then asking for it at work.

Even IBM--a company that pitched the centralized "knowledge management" approach years ago--is experimenting with more lightweight and unstructured collaboration software, including blogs and wikis.

Despite the buzz around Web 2.0 in Silicon Valley, one research firm, called Zoomerang, found more than three-fourths of marketers surveyed were unfamiliar with the term.

And then, only days after the Web 2.0 Summit in San Francisco concluded, The New York Times ran an article proclaiming that Web 3.0 was on the way. The article resurfaced the ideas of Semantic Web, or Web sites that can exchange detailed information about their contents.

--Martin LaMonica

2006 Highlights

MashupCamp--a new kind of get-together

Nearly 300 people show up for a celebration of custom applications and a new-model technology conference.

Yahoo to offer new mashup tools

Company plans to release four application program interfaces for photos, calendar, shopping and bookmark sites.

Web 2.0 stars at PC Forum

Execs, entrepreneurs and policy makers discuss Web 2.0 tech and business models giving users more control and choice.

Gates looks to expand view beyond Windows

At Mix conference, Microsoft appeals to Web developers, commits to more IE updates.

Google buys Web word-processing technology

Showing its interest in enabling people to handle office tasks over the Net, Google buys Upstartle, maker of Writely.

Web 2.0 meets the enterprise

Eager for fresh ideas, the stodgy world of enterprise software is adopting technology and marketing from the consumer Web.

Corporate America wakes up to Web 2.0

Collaboration tools such as blogs and wikis are staking out ground inside businesses--often brought in by the users themselves.

Wikipedia's Wales touts 'free culture' movement

Jimmy Wales urges "Wikipedians" to focus on quality, announces One Laptop per Child project will include Wikipedia on machines.

'Office 2.0' start-ups knock on business doors

Start-ups try to chip away at the Microsoft Office franchise via lower costs and Web-based collaboration.

Google buys JotSpot, dips into wiki world

Search giant expands its hosted application portfolio with purchase of JotSpot, provider of a hosted wiki platform.

Does Web 2.0 bubble have a silver lining?

Not all of today's Web start-ups will survive. But the relatively low cost of a launch means Web services are being developed fast.

Intel unveils Web 2.0 software suite

Chipmaker teams with SpikeSource and others to launch a package of apps for blogs, wikis and social networking.