Higher education is the level of education after the completion of schools (such as high schools, middle schools or gymnasiums) that provide secondary education. Higher education usually includes undergraduate and postgraduate education, as well as vocational education and training. Colleges, universities and technical colleges are the main institutions providing higher education (sometimes collectively referred to as higher education institutions). Institutions providing post-secondary education include vocational schools, community colleges, independent colleges (such as technical colleges) and universities in the United States, technical and continuing education colleges in Australia, CEGEPs in Quebec and IEKs in Greece. They are sometimes collectively referred to as institutions of higher education. Completion of higher education usually leads to a certificate, diploma or degree. Rupert I founded the University of Heidelberg in 1386. Higher education includes teaching, research, strict applied work (such as medical school and dental school) and social service activities of universities. In the field of teaching, it includes both undergraduate level (sometimes called higher education) and postgraduate level (or postgraduate level), and is aimed at qualified students who want to further their education and skills. This level of education is often called graduate school, especially in North America. In the United Kingdom and some other countries (such as Ireland), post-secondary education below the level of higher education is called "continuing education". "Higher education" in Britain usually includes university degree or basic degree education. In many developed countries, a high proportion of people (up to 50%) now enter higher education at some point in their lives. Therefore, higher education is very important to the national economy. It is an important industry in itself and a source of trained and educated personnel in other sectors of the economy. There may be some different opinions on what is higher education, postgraduate education or higher education: "However, it is not always clear what higher education includes. Does it only lead to formal qualifications or may include leisure classes? In Britain, A-levels is a post-compulsory higher education, but is it taught in schools and universities? Is professional renewal or on-the-job training part of higher education, even if it is not after the successful completion of secondary education? " There are two types of higher education in Britain: higher academic education and higher vocational education. Higher education in the United States and Canada refers to colleges and universities that offer associate degree, bachelor degree, master degree, education expert (Ed.S) degree or doctor of philosophy (Ph.D) degree or equivalent, as well as higher professional degrees in the fields of law, medicine, optometry and dentistry. Such institutions may also issue non-degree certificates, indicating that they have completed a set of courses containing some knowledge, but issuing such certificates is not their main purpose. Higher education does not refer to post-secondary education institutions in the United States or Canada. Higher education is a professional education.