Professor (commonly abbreviated as Prof. )  is an academic rank at universities and other post-secondary education and research institutions in most countries. Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences, a teacher of the highest rank. 
The word professor is sometimes used colloquially to refer to anyone in an academic post,  though in most systems of academic ranks , the unqualified word "professor" has a specific definition as the most senior position, sometimes informally known as "full professor".   In some countries or institutions, the word professor is also used in titles of lower ranks such as associate professor and assistant professor .
Professors conduct original research and commonly teach undergraduate , graduate , or professional courses in their fields of expertise. In universities with graduate schools, professors may mentor and supervise graduate students conducting research for a thesis or dissertation . In many universities, 'full professors' take on senior managerial roles, leading departments, research teams and institutes, and filling roles such as President, Principal or Vice-Chancellor . The role of professor may be more public facing than that of more junior staff, and professors are expected to be national or international leaders in their field of expertise.
The term "professor" was first used in the late 14th century to mean "one who teaches a branch of knowledge."  The word comes "...from Old French professeur (14c.) and directly from [the] Latin professor[, for] "person who professes to be an expert in some art or science; teacher of highest rank,"; the Latin term came from the "...agent noun from profiteri "lay claim to, declare openly." As a title that is "prefixed to a name, it dates from 1706." The "[s]hort form prof is recorded from 1838." The term "professor" is also used with a different meaning: "[o]ne professing religion. This canting use of the word comes down from the Elizabethan period, but is obsolete in England." 
A professor is an accomplished and recognized academic. In most Commonwealth nations, as well as northern Europe, the title professor is the highest academic rank at a university. In the United States and Canada , the title of professor is also the highest rank, but a larger percentage achieve it. In these areas, professors are scholars with doctorate degrees (typically Ph.D. degrees) or equivalent qualifications who teach in four-year colleges and universities. An emeritus professor is a title given to selected retired professors with whom the university wishes to continue to be associated due to their stature and ongoing research. Emeritus professors do not receive a salary, but they are often given office or lab space, and use of libraries, labs, and so on.
The term professor is also used in the titles assistant professor and associate professor ,  which are not considered professor-level positions in some European countries. In Australia, the title associate professor is used in place of reader , ranking above senior lecturer and below full professor. 
Beyond holding the proper academic title, universities in many countries also give notable artists, athletes and foreign dignitaries the title honorary professor , even if these persons do not have the academic qualifications typically necessary for professorship and they do not take up professorial duties. However, such "professors" usually do not undertake academic work for the granting institution. In general, the title of professor is strictly used for academic positions rather than for those holding it on honorary basis.
Professors are qualified experts in their field who generally perform some or all the following tasks:
- Managing teaching, research and publications in their departments (in countries where a professor is head of a department);
- Presenting lectures and seminars in their specialties (i.e., they "profess");
- Performing, leading and publishing advanced original research in peer reviewed journals in their fields;
- Providing pro bono community service , including consulting functions (such as advising government and nonprofit organizations) or providing expert commentary on TV or radio news or public affairs programs;
- Mentoring graduate students in their academic training;
- Mentoring more junior academic staff;
- Conducting administrative or managerial functions, usually at a high level (e.g. deans, heads of departments, research centers, etc.); and
- Assessing students in their fields of expertise (e.g., through grading examinations or viva voce defenses).
Other roles of professorial tasks depend on the institution, its legacy, protocols, place (country), and time. For example, professors at research-oriented universities in North America and, generally, at European universities, are promoted primarily on the basis of research achievements and external grant-raising success.
Around the world
Many colleges and universities and other institutions of higher learning throughout the world follow a similar hierarchical ranking structure amongst scholars in academia ; the list above provides details.
A professor typically earns a base salary and a range of benefits. In addition, a professor who undertakes additional roles in their institution (e.g., department chair, dean, head of graduate studies, etc.) earns additional income. Some professors also earn additional income by moonlighting in other jobs, such as consulting , publishing academic or popular press books, or giving speeches or coaching executives. Some fields (e.g., business and computer science) give professors more opportunities for outside work.
Germany and Switzerland
A report from 2005 by the "Deutscher Hochschulverband DHV",  a lobby group for German professors, the salary of professors, the annual salary of a German professor is €46,680 in group "W2" (mid-level) and €56,683 in group "W3" (the highest level), without performance-related bonuses. The anticipated average earnings with performance-related bonuses for a German professor is €71,500. The anticipated average earnings of a professor working in Switzerland vary for example between 158,953 CHF (€102,729) to 232,073 CHF (€149,985) at the University of Zurich and 187,937 CHF (€121,461) to 247,280 CHF (€159,774) at the ETH Zurich ; the regulations are different depending on the Cantons of Switzerland .
The salaries of civil servant professors in Spain are fixed in a nationwide basis, but there are some bonus related to performance and seniority and a number of bonus granted by regional governments. These bonus mean significant differences in the final salary . Some of the bonuses are the "trienios" (depending on seniority, one for each three years), "quinquenios" (depending on the accomplishment of teaching criteria defined by the university, one for each five years of seniority) and "sexenios" (depending on the accomplishment of research criteria defined by the national government, one for each six years of seniority). These bonifications are quite small. However, the total number of "sexenios" is a requisite for being a member of different committees. The importance of these "sexenios" as a prestige factor in the university was increased by the LOU 2001. Some indicative numbers can be interesting, in spite of the variance in the data. We report net monthly payments (after taxes and social security fees), without bonifications: Ayudante, 1,200 euros; Ayudante Doctor, 1,400; Contratado Doctor; 1,800; Profesor Titular, 2,000 euros; Catedrático, 2,400 euros. There are a total of 14 payments per year, including 2 extra payments in July and December (but for less than a normal monthly payment).
Professors in teacher education sometimes earn less than they would if they were still elementary classroom teachers. In one case study report, it was shown that a beginning full-time tenure-track assistant professor in elementary teacher education at California State University, Northridge was hired in 2002 at a salary of $53,000., which was $15,738. less than she would have earned in her previous position as a 9-month public school kindergarten teacher, ($68,738). See Gordon, L. M. (2004, January 6). From kindergarten teacher to college professor: A comparison chart of salaries, work load, and professional preparation requirements. Published proceedings of the Hawaii International Conference on Education. ISSN .
In 2007 the Dutch social fund for the academic sector SoFoKleS  commissioned a comparative study of the wage structure of academic professions in the Netherlands in relation to that of other countries. Among the countries reviewed are the United States, Great Britain, Switzerland, Germany, Belgium, France, Sweden and the Netherlands. To improve comparability adjustments have been made to correct for purchasing power and taxes . Because of differences between institutions in the US and UK these countries have two listings of which one denotes the salary in top-tier institutions (based on the Shanghai-ranking).
Table of wages
The table below shows the final reference wages expressed in net amounts of Dutch Euros. (i.e. converted into Dutch purchasing power). Note that the data might be considered as significantly outdated as of 2017.
|Country||Assistant professor||Associate professor||Full professor|
|United States – top universities||$49,300||$57,142||$87,702|
|United Kingdom – top universities||₤42,245||₤47,495||₤82,464|
In a number of countries, the title "research professor" refers to a professor who is exclusively or mainly engaged in research, and who has few or no teaching obligations. For example, the title is used in this sense in the United Kingdom (where it is known as research professor at some universities and professorial research fellow at some other institutions) and in northern Europe . Research professor is usually the most senior rank of a research-focused career pathway in those countries, and regarded as equal to the ordinary full professor rank. Most often they are permanent employees, and the position is often held by particularly distinguished scholars; thus the position is often seen as more prestigious than an ordinary full professorship. The title is used in a somewhat similar sense in the United States , with the exception that research professors in the United States are often not permanent employees and often must fund their salary from external sources,  which is usually not the case elsewhere.
Traditional fictional portrayals of professors, in accordance with a stereotype , are shy, absent-minded individuals often lost in thought. In many cases, fictional professors are socially or physically awkward. Examples include the 1961 film The Absent-Minded Professor or Professor Calculus of The Adventures of Tintin stories. Professors have also been portrayed as being misguided into an evil pathway, such as Professor Metz, who helped Bond villain Blofeld in the film Diamonds Are Forever ; or simply evil, like Professor Moriarty , archenemy of British detective Sherlock Holmes . The modern animated series Futurama has Professor Hubert Farnsworth , a typical absent-minded but genius-level professor. A related stereotype is the mad scientist .
Vladimir Nabokov , author and professor of English at Cornell , frequently used professors as the protagonists in his novels. Professor Henry Higgins is a main character in George Bernard Shaw 's play Pygmalion . In the popular Harry Potter series, set in a wizard's school called Hogwarts, the protagonists' magic and wizarding teachers are known as professors, many of whom play important roles, notably Professor Dumbledore , Professor Minerva McGonagall , and Professor Severus Snape . In the board game Cluedo , Professor Plum has been depicted as an absent-minded academic. Christopher Lloyd played Plum's film counterpart, a psychologist who had an affair with one of his patients.
Since the 1980s and 1990s, various stereotypes were re-evaluated, including professors. Writers began to depict professors are just normal human beings and might be quite well-rounded in abilities, excelling both in intelligence and in physical skills. An example of a fictional professor not depicted as shy or absent-minded is Indiana Jones , a professor as well as an archeologist - adventurer , who is skilled at both scholarship and fighting. The popularity of the Indiana Jones movie franchise had a significant impact on the previous stereotype, and created a new archetype which is both deeply knowledgeable and physically capable. The character generally referred to simply as the Professor on the television sit com series, Gilligan's Island , although described alternatively as a high-school science teacher or research scientist, is depicted as a sensible advisor, a clever inventor, and a helpful friend to his fellow castaways . John Houseman 's portrayal of law school professor Charles W. Kingsfield, Jr., in The Paper Chase (1973) remains the epitome of the strict, authoritarian professor who demands perfection from students. Annalise Keating (played by Viola Davis ) from the American Broadcasting Company (ABC) legal drama mystery television series How to Get Away with Murder is a law professor at the fictional Middleton University.  Early in the series, Annalise is a self-sufficient and confident woman, respected for being a great law professor and a great lawyer, feared and admired by her students,  whose image breaks down as the series progresses. 
Mysterious, older men with magical powers (and unclear academic standing) are sometimes given the title of "Professor" in literature and theater. Notable examples include Professor Marvel in The Wizard of Oz  and Professor Drosselmeyer (as he is sometimes known) from the ballet The Nutcracker . Also, the magician played by Christian Bale in the film, The Prestige ,  adopts 'The Professor' as his stage name . A variation of this type of non-academic professor is the "crackpot inventor," as portrayed by Professor Potts in the film version of Chitty Chitty Bang Bang or the Jerry Lewis-inspired Professor Frink character on The Simpsons . Other professors of this type are the thoughtful and kind Professor Digory Kirke of C.S. Lewis ' Chronicles of Narnia .
The title has been used by comedians , such as "Professor" Irwin Corey and Soupy Sales in his role as "The Big Professor." In the past, pianists in saloons and other rough environments have been called "professor."  The puppeteer of a Punch and Judy show is also traditionally known as a "professor."