What Is Web 2.0
Source: https://www.oreilly.com/pub/a/web2/archive/what-is-web-20.html ↗
Full text: open-access via OpenAlex ↗
O'Reilly's 2005 essay crystallized a set of patterns that were already emerging — network effects, data as competitive advantage, software as service, users as co-developers — and gave them a name that defined an era of web development.
By contrasting Web 1.0 companies with their Web 2.0 successors (Britannica vs. Wikipedia, Ofoto vs.
Flickr, publishing vs. participation), the essay made legible a shift from the web as a medium for documents to the web as a platform for applications and collective intelligence.
Its influence was immediate and enormous: "Web 2.0" became the organizing concept for a generation of startups, investors, and technologists.
Read today, it is both a historical document of a pivotal moment and a reminder of how much the platform dynamics O'Reilly described have since consolidated into the monopolies he did not fully anticipate.
Still freely available on O'Reilly's site, it repays rereading.
Central argument
O'Reilly argues that Web 2.0 is not a discrete technology upgrade but a structural shift in how software creates value: the network itself becomes the platform, and competitive advantage accrues to those who harness collective user behaviour as a data asset. His central thesis is that the most durable Web 2.0 businesses — Google, eBay, Amazon — succeed because they build systems where every user interaction improves the product, creating compounding network effects through what he calls an 'architecture of participation'. The contrast between Netscape and Google crystallises the argument: Netscape tried to transplant the old desktop software model onto the web, while Google was natively designed around continuous service delivery and data at scale.
Critique
O'Reilly's framework is almost entirely descriptive and retrospective — he identifies patterns in companies that already succeeded and then elevates those patterns into principles, which risks circular reasoning: Web 2.0 is what winning companies did, and winning companies did Web 2.0. More substantially, the essay largely sidesteps the power asymmetries baked into the 'architecture of participation': the same mechanisms that aggregate collective intelligence also concentrate data ownership and market power in platform operators at the expense of the users whose contributions generate that value — a tension that would become one of the defining political and regulatory problems of the following two decades.
Why it matters for product
For a CPO, the essay's core insight — that data generated by users should be treated as a compounding strategic asset, not a byproduct — directly shapes decisions about instrumentation, feedback loops, and what to build first in a product's lifecycle. The Netscape-vs-Google contrast is a useful diagnostic for evaluating whether your own product team is still operating on a 'release and ship' cadence that belongs to the desktop era, rather than designing for continuous improvement driven by usage signals. O'Reilly's 'long tail' argument also has concrete implications for platform and marketplace product strategy: optimising only for your largest users or use cases systematically undervalues the aggregate demand living at the edges of your user base.