The Open University (OU) is a public research university, and the biggest university in the UK for undergraduate education. The majority of the OU's undergraduate students are based in the United Kingdom and principally study off-campus; many of its courses (both undergraduate and postgraduate) can also be studied anywhere in the world. There are also a number of full-time postgraduate research students based on the 48-hectare university campus where they use the OU facilities for research, as well as more than 1,000 members of academic and research staff and over 2,500 administrative, operational and support staff.