Browlser is a "browser" for "OWL", the Web Ontology Language of the semantic web.

Browlser loads an ontology from an XML file and looks inside it for a SWRL rule to tell Browlser how to display it. SWRL is the Semantic Web Rules Language that basically turns the semantic web into a global database query engine. Browlser uses Yield Prolog, a pure Javascript implementation of Prolog, so that all this happens locally in the user's browser. Javascript version 1.7 must be supported by your browser, such as Firefox 3.0.

Try these different views:
Browlser was partly inspired by the availability of Glendon Holst's JScriptLog, which allowed a rules language to run natively in the browser.
See the Browlser Project Page on to get the source and check the status of the project.

Here is a screenshot of the calendar. Remember that Browlser itself doesn't know anything about calendars. The rules for formatting and navigating a calendar are all loaded as rules from the same file as the calendar events.