From Web 1.0 to the Semantic Web

The World Wide Web was invented by Sir Tim Berners-Lee in 1989, a surprisingly short time ago. The key technology of the original Web—from an end user's point of view, anyway—was the hyperlink. A user could click on a link and immediately (well, back then, almost immediately) go to the document identified in that link.

In summary, the great advantage of Web 1.0 was that it abstracted away the physical storage and networking layers involved in information exchange between two machines. This breakthrough enabled documents to appear to be directly connected to one another. Click a link and you're there—even if that link goes to a different document on a different machine on another network on another continent!

The model behind the Web could be roughly summarized as a way to publish documents represented in a standard way (HTML), containing links to other documents and accessible through the Internet using standard protocols (TCP/IP and HTTP). The result could be seen as a worldwide, distributed file system of interconnected documents that humans can read, exchange and discuss.

You can imagine it as a set of books with references to other books or articles: browsing the Web is not really different from going through a book and following its citations to other publications, as described in Introduction to the Semantic Web.

In the same way that Web 1.0 abstracted away the network and physical layers, the Semantic Web abstracts away the document and application layers involved in the exchange of information. The Semantic Web connects facts, so that rather than linking to a specific document or application, you can instead refer to a specific piece of information contained in that document or application. If that information is ever updated, you can automatically take advantage of the update.

This may appear at first to be a very subtle advantage [...]