Terrier is a highly flexible, efficient, and effective open source search engine, readily deployable on large-scale collections of documents. Terrier implements state-of-the-art indexing and retrieval functionalities, and provides an ideal platform for the rapid development and evaluation of large-scale retrieval applications.
Terrier is open source, and is a comprehensive, flexible and transparent platform for research and experimentation in text retrieval. Research can easily be carried out on standard TREC and CLEF test collections.
Terrier is written in Java, and is developed at the Department of Computing Science, University of Glasgow.
Terrier wags its IR tail on verison 3
From the front page of Terrier, which is now at version 3.0 (02010 03 11):