Professors

The meaning of the word professor (Latin: "one who claims publicly to be an expert") varies. In most English-speaking countries, it refers to a senior academic who holds a departmental chair, generally as head of the department, or a personal chair awarded specifically to that individual. In the United States and Canada, professor is simply a polite form of address for any teacher, lecturer, or researcher employed by a college or university, regardless of rank. (See differences and main systems below for more information.)

Professors are qualified experts who may perform the following:
 * conduct lectures and seminars in their field of study (i.e., they "profess"), such as the basic fields of science or literature or the applied fields of engineering, music, medicine, law, or business;
 * perform advanced research in their fields;
 * provide pro bono community service, including consulting functions (such as advising government and not-for-profit entities);
 * train young academics (graduate students).

The balance of these four classic fields of professorial tasks depends heavily on the institution, place (country), and time. For example, professors at highly research-oriented universities in the U.S. (and all European universities) are promoted primarily on the basis of their research achievements.

Differences
The basic difference between levels of professor according to the national academic system is that in the English-speaking countries, the designation is based on career, whereas in Continental Europe, it is based on position. That means that if a North American Assistant Professor is performing particularly well, he or she can be promoted to Associate Professor, and if this is the case again, on to (full) Professor (in the United Kingdom and other countries the ranks are different, but the same principle applies). In the Continental European system, the different fields and sub-fields of teaching and research are allotted certain (professorial) chairs, and one can only become a professor if one is appointed to such a chair (which then has to be free, i.e., unoccupied). Therefore, the different professorial ranks are not necessarily comparable.

Furthermore, "Professor" is also a honorific title, given when appointed to a professor's chair, and retained for life.

Differences may be distinctive in two main groups, "teaching professors" and "research professors" for the same body of knowledge in schools and colleges. There are also "corporate professors" in the work place. For example a student/professional in accounting may have to incorporate many different fields of expertise to be considered adequately trained.

Tenure
A key concept is tenure. A professor who holds tenure is virtually immune to dismissal and has an appointment for life. The reason for the existence of tenure is the principle of academic freedom, which holds that it is beneficial for state, society, and academe in the long run if professors are free to hold and advance controversial views without fear of losing their jobs. Tenure ensures that professors can engage with current political or other controversies. Critics assert that it also means that lazy or unpleasant professors cannot be forced to improve, and has thus recently come under attack from those who want a more business-like approach to universities, including performance review, audits, performance-based salaries, etc.

Main positions

 * Assistant professor: the entry-level position, for which one usually needs a Ph.D. or other doctorate; a master's degree may suffice, especially at community colleges or in fields for which there is a terminal master's degree. In some areas, such as the natural sciences, it is uncommon to grant assistant professor positions to recently graduated Ph.D.s, and nearly all assistant professors will have completed some time as postdoctoral fellows. The position is generally not tenured, although in most institutions, the term is used for "tenure-track" positions; that is, the candidate can become tenured after a probationary period—anywhere from 3 to 7 years. Rates for achieving tenure vary, depending on the institutions and areas of study; in most places at least 50% of assistant professors are tenured and promoted to associate professors after the sixth year; however, this number can be as low as 10% in natural sciences departments of top-10 universities such as Princeton, or over 70% in non-Ph.D. granting schools. In unusual circumstances it is possible to receive tenure but to remain as an assistant professor, typically when tenure is awarded early.


 * Associate professor: the mid-level position, usually awarded (in the humanities and social sciences) after the "second book"—although the requirements vary considerably between institutions and departments. Generally upon obtaining tenure, one is also promoted to associate professor. In relatively rare circumstances, a person may be hired at the associate professor level without tenure. Typically this is done as a financial inducement to attract someone from outside the institution, but who might not yet meet all the qualifications for tenure. If awarded to a non-tenured person, the position is almost always tenure-track with an expectation that the person will soon qualify for tenure.


 * (Full) professor: the senior position. In a traditional school this is always tenured. However, this may not be the case in a for-profit private institution. The absence of a mandatory retirement age contributes to "graying" of this occupation. The median age of American full professors is currently around 55 years. Very few people attain this position before the age of 40. The annual salary of full professors averages around $90,000, although less so at non-doctoral institutions, and more so at private doctoral institutions (not including side income from grants and consulting, which can be substantial in some fields).  Full professors earn on average about 70% more than assistant professors in the same institution. However, particularly in scientific and technical fields, this is still considerably less than salaries of those with comparable training and experience working in industry positions.


 * Distinguished (teaching/research) professor, University Professor, Institute Professor: these titles, often specific to one institution, generally are granted to the top few percent of the tenured faculty (and sometimes to under one percent).

Life of a typical natural sciences professor in United States:


 * Bachelor's degree: age 18–22
 * Ph.D.: 22–28 (rarely takes less than 5 or more than 8 years)
 * Post-doc: 28–32 (highly variable, and multiple post-docs are increasingly common)
 * Assistant professor: 32–38
 * Associate professor: 38–45 (varies)
 * Full professor: 45–70 (professors were forced to retire at 70 during 1986–1993, this is no longer the case; retirement age is now at professors' own discretion; most retire between 65 and 75)
 * Professor emeritus (retired): 70+

Other positions
Professor emeritus: full professors who retire are referred to as Professors Emeriti. This title is also given to retired professors who continue to teach and to be listed; they may also draw a very large percentage of their last salary as pension (as tenure is technically for life). The concept has in some places been watered down to include also associate tenured professors; in some systems and institutions, it needs a special act or vote.

Visiting professor: (also known as sessional instructors) someone visiting another college or university to teach for a limited time; this may be someone who is a professor elsewhere or a distinguished scholar or practitioner who is not. The term may also refer simply to terminal (usually 1–3 years) teaching appointments and/or post-doctorate research appointments (which are much like research internships).

Adjunct professor: someone who does not have a permanent position at the academic institution; this may be someone with a job outside the academic institution teaching courses in a specialized field; or it may refer to persons hired to teach courses on contractual basis (frequently renewable contracts); it is generally a part-time position with a teaching load below the minimum required to earn benefits (health care, life insurance, etc.), although the number of courses taught can vary from a single course to a full-time load (or even an overload).

An adjunct is generally not required to participate in the administrative responsibilities at the institution often expected of other full-time professors, nor do they generally have research responsibilities. The pay for these positions is usually nominal, even though adjuncts typically hold a Ph.D., but most adjuncts also hold concurrent positions at several institutions or in industry.

Adjuncts provide flexibility to the faculty, acting as additional teaching resources to be called up as necessary, however, their teaching load is variable: classes can be transferred from adjuncts to full-time professors, classes with low enrollment can be summarily canceled and the teaching schedule from one semester to the next can be unpredictable (furthermore, if the university makes a good faith offer to an adjunct professor of teaching during the following semester (dependent on enrollment), the adjunct generally cannot file for unemployment during the break). In some cases, an adjunct may hold one of the standard ranks in another department, and be recognized with adjunct rank for making significant contributions to the department in question.

Named chair: a particularly senior full professor who is awarded a specific, endowed chair that has been sponsored by a fund, firm, person, etc. Named chairs are usually similar to the Continental European model in that they are a position rather than a career rank.

Professor by courtesy: a professor who is primarily and originally associated with one academic department, but has become officially associated with a second department, institute, or program within the university and has assumed a professor's duty in that second department as well. Example: "Henry T. Greely is Professor of Law and Professor, by courtesy, of Genetics at Stanford University". Usually the second courtesy appointment carries with it fewer responsibilities and fewer benefits than a single full appointment.

Professor—research: a professor who does not take on all four of the classic duties (see overview) but instead focuses on research. Typically, such a professor may be invaluable to his university department in procuring research funding and/or in publishing scholarly works, and therefore the department would prefer that he not distract himself with teaching duties that are not directly linked to his research activities. Usually research professors must fund their salary entirely or largely through research grants (although this may be the case with any professor who does not teach a full load).


 * By analogy with the above, one often sees assistant or associate research professors, and assistant or associate—but seldom if ever full—teaching professors who focus on teaching and supervising teaching assistants.
 * In some institutions, the teaching and research titles do not exist, though professors will often devote more time to one than the other.

Honorary professor: normally granted to those who have contributed significantly to the school and community. Say, by donation for furtherance of research and academic development.

Gypsy scholar: is an informal term given to some academics who either move several times between institutions and/or work at two or more institutions at a time. There are several possible reasons explaining the existence of gypsy scholars, among these are the fact that many teaching jobs are now either part-time or terminal (1–3 years), with tenure-track positions harder to secure, and also a high cost of housing and living. The latter appears to have become a fairly common situation in California, where the price of housing has skyrocketed (as of 2005). Some faculty teach at more than one institution because their field is so small or specialized that each institution offers only one or two classes in their area. This is particularly common when several small colleges are within driving distance of each other.

In practice, students at many North American universities will both due to habit and out of courtesy refer to any instructor as a "professor" regardless of status, including those holding adjunct or term-limited appointments; exceptions are usually only made in the case of graduate students (graduate teaching assistants), visiting artists, lecturers, and instructors, as these are technically not faculty positions and have no associated titles. Similarly, faculty members are often addressed in speaking as "Professor (name)", although this custom varies by institution and is less observed where the majority of faculty are hired as full-time professors, as there is less need to make a distinction in ranks.

Most other English-speaking countries
See Lecturer and academic rank for an explanation of these titles

In the United Kingdom the Republic of Ireland and most Commonwealth countries (but not Canada, which follows the North American system), equivalently senior academics to assistant and associate professors are generally known as "Lecturers", "Senior Lecturers" and "Readers", with professorships reserved for only the most senior academic staff. A Professor in these countries holds either a departmental chair (generally as the head of the department or of a sub-department) or a personal chair (a professorship awarded specifically to that individual). In that sense, only full professors (North American style) are equivalents of professors. The title of "Professor" is a great honour, normally reserved in correspondence to full professors only; lecturers and readers are properly addressed by their academic qualification (Dr. for a Ph.D., D.Phil. or M.D. and Mr./Mrs./Miss/Ms. otherwise). The style of associate professors is less certain, with some being addressed by their academic qualification and others (perhaps less commonly) as "Professor".

French (France, Belgium)
After the doctorate or a grande école, scholars who wish to enter academia may apply for a position of maître de conférences ("master of conferences").

After some years in this position, they may take an "habilitation to direct theses" [or "to conduct research"] before applying for a position of professeur des universités ("university professor"). In the past, this required a higher doctorate [a "State Degree"]. In some disciplines such as Law, Management ["Gestion"] and Economics, candidates take the agrégation competitive examination. Only the higher-ranked are nominated.

German (Central European)
After the doctorate, German scholars who wish to go into academic are supposed to take a Habilitation, i.e. they write a second thesis mostly on a position as a Wissenschaftlicher Assistent ('scientific assistant', C1) or a non-tenured position as Akademischer Rat ('academic council', both 3+3 years teaching and research positions). Once they pass their Habilitation, they are called Privatdozent and are eligible for a call to a chair. Alternatively a process for acknowledgment by "Junior-Professorship" is possible.

Note that in Germany, there has been always a debate of whether Professor is a title that remains one's own for life once conferred (similar to the doctorate, which becomes part of the legal name), or whether it is linked to a function (or even the designation of a function) and ceases to belong to the holder once she or he quits or retires (except in the usual case of becoming Professor emeritus). The former view has won the day - although in many German Länder, there is a minimum requirement of five years of service before "Professor" may be used as a title without the respective job - and is by now both the law and majority opinion.

When appropriate the joint title "Professor Doktor" has also been heard in the German system.

Similar or identical systems as in Germany (where a Habilitation is required) are in place e.g. in Austria, the German-speaking part of Switzerland, Poland, Slovakia, Hungary and Slovenia.

Main positions

 * Professor ordinarius (ordentlicher Professor, o. Prof.): professor with chair, representing the area in question. In Germany, it's common to call these positions in colloquial use "C4" professorships, due to the name of respective entry in the official salary table for Beamte. (Since the recent reform of the salary system at universities, you might now find the denomination "W3 professor".)


 * Professor extraordinarius (außerordentlicher Professor, ao. Prof.): professor without chair, often in a side-area, or being subordinated to a professor with chair. Often, successful but junior researchers will first get a position as ao. Prof. and then later try to find an employment as o. Prof. at another university. Colloquially called a "C3 professor" in Germany (or in the new scheme: "W2").


 * Professor: In addition to old universities Germany also has Fachhochschulen(FH) as institutions of higher learning, often referred to as universities of applied science. Professors at FH are often looked down on by university professors. Since a new salary scheme has been introduced in 2005, there are both W2 and W3 professors for the Fachhochschulen as there are for the old universities. Hence, the last formal difference has been eliminated.


 * Professor emeritus: just like in Northern America (see above); used both for the ordinarius and for the extraordinarius, although strictly speaking only the former is entitled to be called this way. Although retired and being payed a pension instead of a salary, they may still teach and take exams and often still have an office.


 * Juniorprofessor: an institution started in 2003 in Germany, this is a 6-year time-limited professorship for promising young scholars without Habilitation. It is supposed to rejuvenate the professorship through fast-track for the best, who eventually are supposed to become professor ordinarius. This institution has been introduced as a replacement for the Habilitation, which is now considered more an obstacle than a quality control by many. Being new, the concept is highly debated due to the lack of experiences. The main point of criticism is that the Juniorprofessor is expected to apply for professorships at other universities during the later of the six years, as his university is not supposed to offer him tenure itself (unlike in the tenure track schemes used e.g. in the USA).

Other positions

 * Honorarprofessor: equivalent of the North American adjunct professor, non-salaried.


 * außerplanmäßiger (apl.) Professor: either a tenured university lecturer or Privatdozent to whom the title is given if she or he has not attained a regular professorship after a while, or likewise an adjunct professor. The word außerplanmäßig (meaning "outside of the plan (of positions and salaries)") denotes that he is not paid as a professor but only as a researcher.

Other professors
In the United States, the bestowal of titles on persons is prohibited by constitution. On the other hand, most European governments actively grant different honorifics to their noted citizens. Therefore, the government is actually considered to have a final say in who should be called a professor. This leads to some other uses of professor.


 * Professor as an honorary title: In some countries using the German-style academic system (e.g. Austria, Finland, Sweden), Professor is also an honorific title that can be bestowed upon an artist, scholar, etc., by the President or by the government, completely independent from any actual academic assignment.


 * Gymnasialprofessor (High School Professor): Senior teachers at certain senior high schools in some German states and in Austria were also designated Professor in the late 19th and early 20th century.

Netherlands
The Netherlands essentially conforms the German (Central European) system. Dutch Universities have the possiblitity to appoint extraordinary professors on a parttime basis, typically for 1 day/week or for a few weeks/year. This allows the University to bring in specialized expertise that otherwise would not be available. An extraordinary professor usually has his main employment somewhere else, often in industry or at a research institute or University elsewhere. Such a buitengewoon professor has all the privileges of a full professor (hoogleraar), may give lectures on special topics, or can supervise graduate students who may do their lab work at the place of his main employment.

Israel
The rank system largely parallels the American one, except that there are four faculty ranks rather than three: lecturer (martze), senior lecturer (martze bakhir), associate professor (profesor khaver), and full professor (profesor min ha-minyan). The most junior rank is presently in the process of being phased out: depending on the institution, a candidate is considered for tenure together with promotion to senior lecturer or to associate professor.

Spain
Spain currently employs four categories of tenured (civil servant) positions: Catedrático de Universidad (department head - chair), Profesor Titular de Universidad (professor - department assistant), Catedrático de Escuela Universitaria (fully equivalent in rank and salary to Profesor Titular de Universidad), and Profesor Titular de Escuela Universitaria. This last position category is intended for teachers of technical schools and colleges without a PhD, and is likely to disappear in the near future (the teachers in this category without a PhD will stay in it until retirement, but recruitment will be stopped). The Catedrático de Escuela Universitaria and the Profesor Titular de Universidad categories may be merged by the next reform of the University Law. The two Escuela Universitaria categories are intended to teach mainly in courses of three year duration (engineering technician courses, nursing, and primary school teaching studies among others) without the possibility of continuing postgraduate studies, while the two Universidad categories teach in courses of four and five years duration.

Professors belonging to the Catedrático and Professor Titular de Universidad categories have the same rights, both can have collaborators and manage money, and may become deans or department directors, but the net salary of a catedrático is about a  15% higher than that of a professor titular of the same seniority. Only a Catedrático de Universidad can become rector of a university. Although in the past people could become catedrático or professor titular with a random curriculum, because local support was the most important requirement for a candidate, independently of his/her research or teaching quality, the present habilitation law, which requires to pass a habilitation examination at the national level for each category before applying to a position, has increased the necessary standars to become a university professor of any of the categories to the level required in other developed countries. If a professor has a PhD and holds any of the four main tenured ranks, he or she has full academic freedom in their respective department.

Spain is not an easy country for foreign people. People with a foreign diploma (even if they are Spanish citizens) must apply for its equivalence with any of the current Spanish diploma to the Spanish Ministry of Education and Science, first for the Bachelor or Master diploma, and when the equivalence for this first diploma is granted, they must apply  for the equivalence of the PhD diploma. These steps  can last three years or more, and may fail if the subjects studied in the first diploma are too differents from those required for the closest Spanish diploma. For nationals of the European Community there is a somewhat faster procedure called recognition (which may also fail). People with a bachelor diploma having completed a PhD immediately afterwards (that is, skipping a two years master) have found impossible to get the equivalence of their diploma, because a bachelor last three years and the Spanish diploma leading to a PhD last at least four years. To actually become a professor, a candidate must a be a national of one of the  the European Community countries, or to be married to one of them. A good knowledge of the Spanish language may be required, and also of the local language in Catalonia, Galicia and the Basque Country. In regions with a local language (Catalonia, Balear Islands, Valencia, Basque Country and Galicia), teaching at the university level is sometimes done in the local language, almost exclusively in Catalonia.

Tenure is associated to the civil servant (funcionario) condition. A civil servant, like in other continental countries, cannot be fired even in case of remarkably bad performance. Since recently, some permanent, although non tenured, positions can be created by the universities (Profesor Contratado Doctor). This possibility has been used mainly by the Catalan universities although others universities have also used these ranks to a lesser degree.

Salary of professors (USA, Germany, Switzerland)
In interest of an expert's report from 2005 of the „Deutscher Hochschulverband DHV“, a lobby of the German professors, the salary of professors in the United States, Germany and Switzerland is as follows:


 * The actual salary of a German professor is 46.680 Euro p.a. in group „W2“ (mid level) and 56.683 Euro p.a. in group „W3“ (highest level), without performance-related surcharges. The anticipated average earnings with performance-related surcharges for a German professor is 71.500 Euro.
 * In the United States of America the anticipated average salary is $98,000 (81.919 Euro) at a public university and $127,000 (106.161 Euro) at a private university.
 * The anticipated average earnings of a Swiss professor oscillate for example between 102.729 Euro (158.953 CHF) to 149.985 Euro (232.073 CHF) at Zurich University and 121.461 Euro (187.937 CHF) to 159.774 Euro (247.280 CHF) at Swiss Federal Institute of Technology in Zurich (ETHZ); the regulations are different depending on the Cantons of Switzerland.

Professors in fiction
In fiction, in accordance with a stereotype, professors are often depicted as being shy and absent-minded. An obvious example is the 1961 movie The Absent-Minded Professor. Professors have also been portrayed as being misguided, such as the one who helped the villain Blofeld in the James Bond film Diamonds Are Forever, or simply evil like the Professor Moriarty who fought Sherlock Holmes. Animated series Futurama has a typical absent-minded but genius Professor Hubert Farnsworth. (see also mad scientist). Some other professors, like Professor Lidenbrock in Journey to the Centre of the Earth. Author and professor of English at Cornell Vladimir Nabokov frequently used professors as the protagonists in his novels.

An example of a fictional professor not depicted as shy or absent-minded is Indiana Jones, a professor as well as an archeologist-adventurer.

Quotes

 * "Lectures," said McCrimmon, "are our most flexible art form. Any idea, however slight, can be expanded to fill fifty-five minutes; any idea, however great, can be condensed to that time. And if no ideas are available, there can always be discussion. Discussion is the vacuum that fills a vacuum. If no one comes to your lectures or seminars, you can have a workshop and get colleagues involved. They have to come, and your reputation as an adequately popular teacher is saved."
 * John Kenneth Galbraith, A Tenured Professor