Disciplines vary between well-established ones that exist in almost all universities and have well-defined rosters of journals and conferences, and nascent ones supported by only a few universities and publications. A discipline may have branches, and these are often called sub-disciplines.
The following outline
is provided as an overview of and topical guide to academic disciplines. In each case an entry at the highest level of the hierarchy (e.g., Humanities) is a group of broadly similar disciplines; an entry at the next highest level (e.g., Music) is a discipline having some degree of autonomy and being the basic identity felt by its scholars; and lower levels of the hierarchy are sub-disciplines not normally having any role in the structure of the university's governance.