A Doctor of Philosophy (Ph.D. or D.Phil.) is a type of doctorate degree awarded by universities in many countries. Ph.D.s are awarded for a wide range of programs in the sciences (e.g., biology, physics, mathematics, etc.), engineering, and humanities (e.g., history, literature, musicology, etc.), among others. The Ph.D. is a terminal degree in many fields. The completion of a Ph.D. is a requirement for employment as a university professor, researcher, or scientist in many fields. A clear distinction is made between an "earned doctorate", which is awarded for completion of a course of study and a thesis or dissertation, and an "honorary doctorate", a title granted by a university to a successful or notable person who has not completed doctoral academic work or completed a dissertation at t