I have wanted to understand things like the semantic web, RDF, OWL and how these things fit with XBRL (or how XBRL fits with these things) for some time. Someone recommended the book Semantic Web for Dummies, so I pieced that up and am making my way through it. I certainly don't have all this figured out yet, but there are some things which are very clear.
Semantic Web
So, the Semantic Web is basically a "database in the sky". It is super-metadata. It allows data stored in different formats and systems to all "look" like one database, one system. This enables easy access to the information using web standards. It enables reuse of information, allowing anyone to "remix" the data.
Semantic Web (capital) and semantic web (lower case)
The "Semantic Web" and "semantic webs" are different things. This is just like the difference between the Internet, intranets, and extranets. "The Semantic Web" (upper case) will be sitting out there in cyberspace just like the Web is sitting there and available for all to use. The Web and the Semantic Web will co-exist and they serve different purposes really.
Companies will also have "semantic webs" (lower case). These will be private, for internal use only by employees of a company, like an intranet. Companies will participate in other "semantic webs" with suppliers and customers, much like an extranet.
EDGAR as compared to IDEA
The SEC EDGAR system has been described as"one of the federal government's most valuable and important databases". However, EDGAR does not fit into the Semantic Web or even into semantic webs. The best that the EDGAR system can do is get you to documents which relate to a company. The database cannot get you INSIDE the document, to get to the information from the document. EDGAR is a big filing cabinet. There is some value in providing semantic information to get you to the EDGAR filings, but that will leave people wanting. For example, Edgar Online spends probably millions of dollars writing parsing algorithms to get what people really want, the information in the documents.
Now IDEAwill be part of the Semantic Web. IDEA is a database (or will be once filings start coming in starting in June/July 2009). You can get inside the documents, to the information reported by companies. If EDGAR was valuable (which I believe it is); IDEA will be killer!
XBRL and the Semantic Web
So, what does XBRL provide to the Semantic Web or to semantic webs?
That is what I see thus far.