Basically, you type in a search term/phrase. The results come back with a color-coded listing of generally how many titles are in each of the ten Dewey classes. Hover over the class name and you’ll get the number of titles in that class. Click on the class you want and the next layer of classes appears, color-coded and with the number of titles. Click on the section you want and you will get a third layer, similar to the others. Click on this third layer and you will see citations which link back to the record in the database you are searching.
You can use Boolean AND (all of the keywords) or OR (any of the keywords), and limit by language. You can also change the language of the Dewey captions.
Right now, this is a prototype, but it could be really helpful when searching your online catalog, or a digital repository, or a huge database like OCLC’s.
[FYI — I work for an OCLC regional service provider.]