In the US, academic degrees and titles evolved from two main sources: the Medieval European universities, founded in the 11th-13th centuries CE, and Humboldt University of Berlin, founded in the 19th century, which provides the model for a “research university.” This means that a lot of the terminology is borrowed from Latin and certain terms mean different things in different contexts.

The purpose of this page is to explain some key terms. Note that I’m focused on the US here! Other countries have different higher education systems and traditions. Some are pretty similar (Canada), others are very different (contemporary France and Germany).


Degrees are divided into “undergraduate” and “graduate,” where “graduate” means that you do it after receiving a Bachelor’s degree.


  • Associate’s: Also called a two-year degree, because it normally takes two years on a full-time class schedule. Generally speaking, schools that award Master’s degrees don’t award Associate’s degrees.

  • Bachelor’s: Also called a four-year degree, because it normally takes four years on a full-time class schedule. If you transfer with an Associate’s degree, it normally only takes two more years; this is part of the California Master Plan for Higher Ed.


Graduate degrees are further divided into “professional” and “academic” (or “research”) degrees. Professional degrees are focused on preparing students for a career in a specific profession, such as teaching, medicine (including nursing and physical therapy), or law. Academic degrees are focused on developing expertise in a specific area of knowledge/research.

  • Master’s: A Master’s program typically takes 1 to 3 years. Some professional Master’s programs will be combined with a certification process, such as for teaching or nursing. The exact requirements vary a lot between kinds of programs. Some Master’s programs are entirely based on courses; to get the degree you just need to get passing grades in all of the courses. Some might have a practical component, like an intership; social work, teaching, and physical therapy programs often work like this. Other Master’s programs require writing a thesis or passing a comprehensive exam.

  • Doctorate: Formally, “doctorate” usually means that this is the highest degree available in a field, professional or academic. For example, there are no further degrees to get beyond a MD (the degree to become a physician) or JD (the degree to become a lawyer). But MD and JD programs usually don’t require research, so they work more like Master’s programs than PhD programs.

  • PhD: A PhD is the highest degree in an academic field. Typically, getting a PhD involves first getting a Master’s degree in the field, passing a major exam (often called a “qualifying exam” or “quals”), and then conducting original research in a dissertation or thesis. Typically, conducting the original research and writing the dissertation takes 3-5 years, though often it can take quite a bit longer. Some fields may use a slightly different name for their doctorate, such as EdD for “doctorate of education.”

Most college faculty (professors and instructors) have a PhD, though not all.

Titles and Ranks

In the US, Bachelor’s and Master’s degrees don’t give you any special title. MDs and PhDs get the title “Doctor.” Traditionally, when your PhD dissertation is accepted, your advisor gives you the good news by greeting you with “Congratulations, Dr. Yourname.” However, some media outlets only use “Doctor” for people with MDs, because in everyday English “doctor” usually means “medical doctor.”

Using titles can be tricky. Some faculty think being called “Doctor So-and-so” is too formal. At the same time, a lot of people have the bad habit of addressing men faculty as “Professor Lastname” or “Doctor Lastname” but addressing women faculty as “Firstname” or “Miss [or] Mrs. Lastname.” This unequal treatment is disrespectful. So, unless someone has told you what titles to use, it’s safest to use “Professor [or] Doctor Lastname.”

To understand ranks (the different kinds of professor), you first need to understand the tenure system. When a faculty member has tenure, they basically have very high job security. It’s not impossible to fire them, but it’s very very hard. In most higher education systems, getting tenure requires doing high-quality work in four areas: research, teaching, and service (doing things like serving on university committees and contributing to peer review). Research schools tend to put more emphasis on research (though teaching is also somewhat important), while teaching schools tend to put more emphasis on teaching (though research is also somewhat important). In the UC system, getting tenure also requires doing high-quality work in diversity, equity, and inclusion.

Not all faculty members are on the tenure system (or “tenure track”). In fact, across the country, non-tenure-track faculty do most of the teaching in higher education today. Non-tenure-track faculty have much less job security — they might not even be guaranteed a job from semester to semester — and often have fewer resources and limited opportunity to work with graduate students. However, typically tenure-track and non-tenure-track faculty have exactly the same qualifications. (Understanding why non-tenure-track positions are so common is a complex story I won’t go into here.)

Non-Tenure Track Faculty

  • Some common titles for non-tenure track faculty include visiting assistant professor, adjunct professor, instructor, and lecturer.
  • The UC system also has the title of Teaching Professor. Teaching Professors have high job security and some of the same rights as tenure-track faculty, but aren’t expected to do research.

Tenure-Track Faculty

  • Assistant Professor: Tenure-track faculty who haven’t received tenure yet. This is kind of a probationary period: show us how good you are, and we’ll give you tenure. Typically a faculty members applies for tenure after 6 years as an assistant professor.

  • Associate Professor: The first rank of tenured faculty. Usually a faculty member needs to be tenured (associate or full professor) in order to serve in roles such as a department or program chair.

  • Full Professor: Full professors are tenured faculty who are highly distinguished in their field. Typically associate professors can apply to be full professors after 6 years. While full professors have more prestige and better pay than associate professors, there usually aren’t significant differences in terms of formal power.

Research Positions

  • Postdoctoral researchers or postdocs are people with PhDs (post- or after the doctorate) who work as full-time researchers and do little or no classroom teaching. Generally postdocs are attached to the research lab of a tenure-track faculty member, and have contracts that last from 1 to 3 years. Most postdocs are hoping to land a tenure-track job before their contract ends, though some researchers move from postdoc to postdoc for several years.

  • Research professors are like postdocs with longer-term contracts. Like postdocs, research professors do no or little teaching. Research professors are often supported entirely by external research grants, which last for 3-5 years. Research professors will often have multiple active grants at any one time, so that they won’t lose their job when a grant expires.

  • Primary Investigator or PI is the lead researcher on a research grant. They’re almost always a tenure-track faculty member or research professor, and usually they’re in charge of a lab space with various students, postdocs, and research staff.