Higher education in the United States is an optional stage of formal learning following secondary education. Higher education, is also referred as post-secondary education, third-stage, third-level, or tertiary education. It covers stages 5 to 8 on the International ISCED 2011 scale. It is delivered at 4,360 Title IV degree-granting institutions, known as colleges or universities. These may be public or private universities, liberal arts colleges, community colleges, or for-profit colleges. US higher education is loosely regulated by several third-party organizations.