A public university is a university that is predominantly funded by public means through a national or subnational government, as opposed to private universities. A national university may or may not be considered a public university, depending on regions. In some regions of the world prominent public institutions are highly influential centers of research; many of these universities are ranked among the best in the world by THES - QS World University Rankings and the Academic Ranking of World Universities, including the University of California, Berkeley, McGill University, Swiss Federal Institute of Technology Zurich, the University of Wisconsin-Madison, and Imperial College London.