all representations have essentially the same information content. And what we mean by "essentially" allows in fact some wriggle room, and in the end it rests on a common understanding between publisher of the information and quoter of the URI. The sameness we are after is the sameness of information content. That is what is identified by the URI. That is why we say that the URI identifies that conceptual information content, irrespective of its particular representation: the conceptual work. Without that common understanding, the web does not work. Some people have said, "If we say that URIs identify people, nothing breaks". But all the time they, day to day, rely on sameness of the information things on the web, and use URIs with that implicit assumption. As we formalize how the web works, we have to make that assumption explicit.

It demonstrates the ambiguity of natural language that no significant problem had been noticed over the past decade, even though the original author or HTTP , and later co-author of HTTP 1.1 who also did his PhD thesis on an analysis of the web, and both of whom have worked with Web protocols ever since, had had conflicting ideas of what the various terms actually mean.

an HTTP URI may identify something with a vagueness as to the dimensions above, but it still must be used to refer to a unique conceptual object whose various representations have a very large a mount in common. Formally, it is the publisher which defines the what an HTTP URI identifies, and so one should look to the publisher for a commitment as to the exact nature of the identity along these axes.