Like many terms of art, “Web 2.0″ tends to be used with alarming promiscuity by technology startups and their marketing departments. Read on to find out:

• What is Web 2.0 and why is it important? (executive summary)
• So, what else is Web 2.0? (detailed answer)
• Why is the distinction meaningful? Isn’t Web 2.0 really just marketing hype?

What is Web 2.0 and why is it important? (executive summary)

Web 2.0 loosely refers to the new generation of tools, technologies, and Websites that sprung up in the early 2000s, after the dot-com bubble burst, when our daily experience of the Web began changing in a subtle but important way.

More of a business concept than a precise technical term, Web 2.0 is about the evolution from packaged software programs—the kind that you install on to your computer—to programs that you simply access inside a Web browser (i.e., Outlook vs. Gmail). The Web is now the important platform, not the PC—just as the PC replaced the mainframe before it.

Still hazy? If you mentally replace “Web 2.0″ with “fancy, new-fangled sh**” you’ll be pretty close to accurate.

So, what else is Web 2.0? (Detailed answer)

As stated above, any Web 2.0 definition is going to be a little fuzzy since it doesn’t refer to a specific, identifiable piece of technology. However, a good guideline for determining whether something is a Web 2.0 technology is to apply The Three C’s of Web 2.0: (1) Cloud computing; (2) Collaborative content; and (3) Collective contributions. These are overlapping and interrelated concepts that fundamentally describe whether something operates according to the Web 2.0 paradigm.

The Three C’s of Web 2.0

1. Cloud computing. Performing and saving your entirely within the Web browser is also called “cloud computing,” since it’s performed in the Internet cloud rather than on your PC. The old model of Client/Server called on installing different pieces of software for each application; with Web 2.0, an increasing number of productivity tasks can be performed entirely within one piece of software, the Web browser.
2. Collaborative content databases.  In the end, an application is really just window dressing that allows us to control what’s really important: data. Documents, emails, customer lists, sales data, videos, graphics… this is all data, and it’s the lifeblood of our work. Web services and APIs allow data to be imported, exported, and manipulated by other Web 2.0 applications that live in the cloud; for example, YouTube video embedded in a blog, or a SalesForce.com mail merge with Google Docs.
3. Collective contributions from everyone. In the early days, the Web was read-only; some few publishers would create content  and the rest of us would browse it. Early e-commerce followed the same one-to-many model. In the world of Web 2.0, everyone is a publisher and contributor: blogging, tagging, reviewing, and even editing Websites on the fly. Web 2.0 is a real-time collaboration of many-to-many.

The more a  Website demonstrates these Three C’s—Cloud computing, Collaborative content, and Collective contributions—the more it can be said to be a Web 2.0 application.

A more thorough and technically-oriented definition of Web 2.0 is offered by Tim O’Reilly in his essay “What is Web 2.0? Design Patterns and Business Models for the Next Generation of Software.” O’Reilly is an extremely credible authority, having been as responsible as anyone for popularizing the phrase. He includes a more granular list of technologies that help to designate whether or not something is Web 2.0.

Since there is no single, identifiable technological breakthrough at the heart of Web 2.0, it’s easy to dismiss the term as merely marketing fluff. But the fact is, Web 2.0 has a fairly unique and helpful meaning¹ that allows us to communicate with each other more efficiently. Here’s an anecdote from Tim O’Reilly to this point:

…at Esther Dyson’s PC Forum last March, after presentations by two startups showing shared calendaring services, I overheard one attendee say to another, “xxx is so Web 1.0, and yyy is so Web 2.0″ and the other attendee knew exactly what he meant. A meme is a pointer, and as long as it points in the right direction, so that the listener recognizes what is being pointed at, it works.

So while it’s technically accurate to note that (i.e.) blogging software and tag clouds could have been jury-rigged together in 1995 using the primitive Web development tools of the day, it’s also missing the point. Web 2.0 isn’t just about the specific technical tools, it’s also about the larger sociological factors that underlie how people are collectively using the Web, and the differences in our doing so from (say) 1995-1999 to 2005-2009; a fundamental and widespread paradigm shift, in other words. Instead of saying all of that every time, it’s easier to just shorthand the idea to Web 2.0.² 

Other FAQs (coming soon!)

I’m still working to import my previous drafts of this FAQ from other sources, and appreciate everyone’s patience in the meantime! In the near future, Bits & Bytes 2.0 will also be addressing:

• What is the difference between Web 1.0 and Web 2.0?
• What is Web 3.0? Does it exist yet?
• What does Web 2.0 mean for entrepreneurs?
• Which Web 2.0 applications and/or Web 2.0 strategies can help run my small business?

1. Contrast the relatively clear meaning of Web 2.0, upon which there is a general agreement, with truly useless-yet-widespread terms like ‘enterprise-wide solution.’ Or try asking two different English majors to define ‘post-modernism’ for you! [↩]
2. Skepticism about the term comes largely from two sources: language purists and Internet old-timers. In the first case, my personal bias tends toward descriptive linguistics, rather than prescription, since I think the primary purpose of language is to communicate successfully rather than hew to some academic ideal. In the case of Internet old-timers, arguments that boil down to yelling “get off my lawn!” at every new trend tend to be pretty unconvincing. [↩]