make a college. It is an adherence to the residential scheme of things." Yet the federal principle has also been called the "Cambridge principle", and is sometimes seen as essential to a collegiate university. There is also dispute as to what is meant by a federal university: some writers have argued that the distinct feature of a federal system is the separation of teaching and examination, but others see the distinction as being one of governance and distribution of authority. A distinction is sometimes made between federal universities, collegiate universities (where the college is the primary academic unit, i.e. Oxford and Cambridge) and universities that have residential colleges but where these do not participate in teaching. One definition of a collegiate university states that "it’s the sense of community within a big environment that’s the common feature". Collegiate universities with centralised teaching In many collegiate universities, the teaching is centrally organised through departments and faculties on a university-wide basis. The level of participation in teaching of colleges in such universities varies: they may provide no formal teaching (e.g. Durham), may provide some teaching to their own students (the Oxbridge model), may provide some teaching that is available university or faculty-wide (e.g. Toronto), or may be responsible for delivering centrally organised, university-wide teaching (e.g. Roehampton). Whatever their role in teaching, almost all are residential communities and they will often have their own halls for meals, libraries, sports teams and societies; such colleges are thus sometimes termed residential colleges. Monash University in Australia has, however, developed a non-residential college model, and New York University has similar "learning communities" to support non-residential students. The specifics of how the collegiate system is organised – whether college membership is necessary for students, whether colleges are legally independent, the role colleges play in admissions, etc. – vary widely between different universities. While the ancient universities of Oxford and Cambridge consist of independent colleges that supplement the university's teaching with their own tutorials, some universities have built colleges that do not provide teaching but still perform much of the housing and social duties. Such colleges are planned, built and funded entirely by the central administration and are thus dependent on it, however they still retain their own administrative structures and have a degree of independence. This system was pioneered at Durham University in the United Kingdom in the 1830s, and has been described as "a far better