IBM Semantics Toolkit "The semantics toolkit contains three main components (Orient, EODM, and Rstar), which are designed for users of different levels.
1. Integrated Ontology Development Toolkit (Orient), as a visual ontology management tool, is mainly used by domain experts who have limited computer knowledge but who are familiar with specific domain knowledge. It is designed as a set of loosely-coupled cooperative Eclipse plug-ins. Orient can now run on Eclipse 3.0 or compatiable software. Orient is a joint R&D project of IBM China Research Laboratory, Beijing, and APEX Data and Knowledge Management Lab, Shanghai Jiao Tong University.
2. Extended Ontolgy Definition Metamodel (EODM) and RDF Repository Star (RStar) provide a set of programming APIs for programmers and IT specialists. EODM is designed to provide a high performance OO interface for the programmer. Now, it is mainly used to manage ontology-level data with limited size.
3. RStar is used for storing and querying mass data, most of which belong to the instance level. In such a situation, the programmer will use SQL-like sentences to manipulate data."
"RStar provides a high-performance RDF storage and query system. It can takes RDF/XML files or RDF triples as input for loading ontology and instances. It accepts queries in the RStar Query Language and returns results as tables. It supports RDF(S) inference. Currently, RStar uses relational database as its back-end storage."
From, Semantic Web Interest Group IRC Scratchpad.