Doctorate
A Doctorate (Ph. D., M.D., D.C., J.D.) is the highest earned degree awarded by a University.
In the nineteenth century, first in Germany and later in other nations in Europe and in the United States, the degree of "Doctor of Philosophy" (Latin "Philosophiae Doctoris", thus Ph. D.) was established as the final result of an program of advanced study, culminating in a dissertation or formal (not always published) work. Though originally awarded only in Philosophy, the Ph. D. is now also awarded in numerous fields of the Humanities and Sciences.
In the early days of the University movement, the title "Doctor" (Latin for "Teacher" was only honorary, and typically awarded for some achievement of note in the outside world, such as when Samuel Johnson was awarded a Doctorate in Letters (L.L.D.) by Oxford for his work on his Dictionary.
Honorary Doctorates are still awarded, but are not considered the equivalent of "earned" doctorates obtained through study and original research.
People who have earned their doctorate are entitled to use the honorific "Doctor."
Doctoral fraud
The confusion amongst the public between academic and medical doctors can lead to the practise of Doctoral fraud, where the holder of an academic Ph.D. (especially one that has been purchased from a non-accredited college) deliberately misrepresents themself as an M.D. in order to enhance their expert standing or the supposed legitimacy of a pseudo-medical commercial enterprise. For example the nutritionist Gillian McKeith calls herself a Doctor on this basis alone [1] [2]; the theological doctorate of the prominent Northern Irish political leader Ian Paisley comes from an equally dubious source [3]. Likewise, children's author Dr. Seuss never completed his doctoral degree in literature.[1]