On Wed, Aug 03, 2011 at 02:40:52PM -0400, Dalkandura Arachchige Gunaratna wrote:
For example, "Populated places" does not return any category listing for the query but if you search Wikipedia, it gives categories.
No it doesn't. http://en.wikipedia.org/w/index.php?title=Populated_places&redirect=no
Perhaps you did not notice you followed a redirect to [[Populated place]], no 's'?
If you want the API to follow redirects, add '&redirects' to your query:
http://en.wikipedia.org/w/api.php?action=query&prop=categories&title...