IBM Web Ontology Manager (WOM) is a lightweight, J2EE Web-based system for managing Web Ontology Language (OWL) ontologies. WOM enables developers to browse or search the ontologies registered with the system by class or property names. In addition, they can submit a new ontology file.

An ontology (in computer science terms, from Wikipedia), is "a data model that represents a domain and is used to reason about the objects in that domain and the relations between them." Wikipedia has a number of links that are useful for those interested in the domain.

Have you done any work with ontologies? Have you any interest in the domain?

Ontologies are indeed a very interesting topic in the times of internet information chaos, web 2.0 trends and the real world working acting like a network, but using the term "lightweight" together with words "J2EE" and "IBM" sounds really funny :)

I've looked at Jena2 source in depth several times over the last 2 years and it's horrible. Why would anyone want to use it? Jena2 claims it's RETE, but it doesn't look like RETE.

A non technical explanation of Ontology might be this. An Ontology is like a card catalog, which organizes information into some structure. For example, in Biology there's genus, phylum and kingdom.

peter

Your explanation for an Ontology is not quite correct. You are really describing a taxonomy. An Ontology specifies a conceptualization of the world, including classes and properties. The main difference between ontologies and taxonomies is that individuals (things) can be *instances* of the classes in an ontology. In a taxonomy, for example, I can not be an instance of a genus even though I may be classified under some genus.

Thanks for pointing out that subtle difference. hopefully my dumbed down explanation isn't too gross. It's been quite a while since I've looked at the subtle differences between taxonomy and ontology. My foggy memory is there are a few other minor differences between the two, but I honestly can't remember them. my brain is full of wholes and doesn't retain data well.

peter

An Ontology specifies a conceptualization of the world, including classes and properties. The main difference between ontologies and taxonomies is that individuals (things) can be *instances* of the classes in an ontology.

plus ... an ontology may contain relations and axioms (both are not available in a taxonomy)

In a summary - a taxonmy is a special subset of an ontology

An Ontology specifies a conceptualization of the world, including classes and properties. The main difference between ontologies and taxonomies is that individuals (things) can be *instances* of the classes in an ontology.

plus ... an ontology may contain relations and axioms (both are not available in a taxonomy)In a summary - a taxonmy is a special subset of an ontology

I agree with the comments pointing out the subtle differences between ontology vs taxonomy. Look like my dumbed down explanation was way too superficial. atleast it generated some comments.

peter

Seems like an ontology browser similar to Swoop.

The impression I get is that ontologies are ready for use right now for the specific use of 'canonicalizing' read-only information. Ie search, content management, etc.

I think it's quite easy to erroneously overextend the concept as a generalized model/metadata format. The semantics of OWL are very formally defined and seem to preclude strict validation of data or any notion of activity.

I expect that initiaves around ontologies in the webservice space might hit some of these limitations. Maybe I'm wrong.

And performance can be a large gotcha too.