To provide a WWW-queryable interface, the Broker needs to run in conjunction with an HTTP server. Since installing an HTTP server can sometimes be difficult, you might also want to look at the list of Frequently Asked Questions on the subject. The instructions from the Harvest binary software distribution describe how to configure your HTTP server to work with Harvest.
You can run the Broker on a different machine than your httpd runs on, but if you want users to be able to view the Broker's content summaries then the Broker's files will need to be accessible to httpd. You can NFS mount those files or manually copy them over. You'll also need to change the Broker's query.html to point to the host that is running the Broker.