In the United States and Canada, an academic major or major concentration (informally, major or concentration) is the academic discipline to which an undergraduate student formally commits. A student who successfully completes the courses prescribed in an academic major qualifies for an undergraduate degree.
In US, in the second half of the 19th century, concentrated focuses at the undergraduate level began to prosper and popularize, but the familiar term “major” did not appear until 1877 in a Johns Hopkins University catalogue. The major generally required 2 years of study. The Minor, required one. Abbott Lawrence Lowell introduced the academic major system to Harvard University in 1910, during his presidency there. It required students to complete courses not only in a specialized discipline, but also in other subjects. Variations of this system are now definitive among tertiary education institutions in the United States and Canada.
Today, an academic major typically consists of a core curriculum, prescribed courses, a liberal arts curriculum, and several elective courses. The amount of latitude a student has in choosing courses varies from program to program. Typically, the courses of an academic major are portioned in several academic terms.
A major is administered by select faculty in an academic department. A major administered by more than one academic department is called an interdisciplinary major. In addition, some students design their own major, subject to faculty approval.
Whereas some students choose a major when first enrolling as an undergraduate at a school, others choose one later. Some schools even disallow students from declaring a major until the end of their second academic year.
A student who declares two academic majors is said to have a double major. A coordinate major is an ancillary major designed to complement the primary one. A coordinate major requires fewer course credits to complete. (Compare with academic minor and joint honours.)
History of the Academic Major and its Development
The roots of the Academic major as we now know it, first surfaced in the 19th century as “alternative components of the undergraduate degree.”  Before that, all students receiving an undergraduate degree would be required to study the same slate of courses geared at a comprehensive “liberal education.”  In 1825, the University of Virginia initiated an educational approach that would allow students to choose, from eight options, an area of focus (ex: ancient languages, anatomy, medicine) and higher educational systems in Europe after the American civil war developed further into a stricter specialization approach to studies.  In US, in the second half of the 19th century, concentrated focuses at the undergraduate level began to prosper and popularize, but the familiar term “major” did not appear until 1877 in a Johns Hopkins University catalogue. The major generally required 2 years of study. The Minor, required one. From 1880 to 1910, Baccalaureate granting American institutions vastly embraced a free-elective system, where students were endowed with a greater freedom to explore intellectual curiosities. The 1930s witnessed the appearance of first interdisciplinary major: American studies. Culture was the grounding concept and orchestrating principle for its courses.  1960s to 1970s experienced a new tide of interdisciplinary majors and a relaxation of curriculum and graduation requirements. (civil rights movements spawned Women’s studies and Black Studies, for example.)  In the 1980s and 1990s, “interdisciplinary studies, multiculturalism, feminist pedagogy, and a renewed concern for the coherence and direction of the undergraduate program began to assail the Baccalaureate degree dominated by the academic major.” 
The Major's Significance
The academic major is considered a defining and dominant characteristic of the undergraduate degree. “The ascendancy of the disciplines in the late nineteenth century and their continuing dominance throughout the twentieth century have left an indelible imprint on the shape and direction of the academic major” and research affirms that the academic major is the strongest and clearest curricular link to gains in student learning.  While general education is considered to be the breadth component of an undergraduate education, the major is commonly deemed as the depth aspect. 
Discourse and Disagreement
Through its development, scholars, academics, and educators have disagreed on the purpose and nature of the undergraduate major. Generally, proponents of the major and departmental system “argue that they enable an academic community to foster the development, conservation and diffusion of knowledge.” While critics “claim that they promote intellectual tribalism, where specialization receives favor over the mastery of multiple epistemologies, where broader values of liberal learning and of campus unity are lost, and where innovation is inhibited due to parochial opposition to new subspecialties and research methods.” 
- Rudolph, Frederick. Curriculum: A History of the American Undergraduate Course Study Since 1636. San Francisco: Jossey Bass, 1977. Print.
- McGrath, Charles (8 January 2006). "What Every Student Should Know". The New York Times (The New York Times Company). Retrieved 23 September 2011.
- "The Academic Major.” Encyclopedia of Education. Ed. Guthrie, James W. 2nd ed. Vol. 1. New York: Macmillan Reference USA, 2006. 19-23.
- Conrad, Clifton F. The Undergraduate Curriculum: A guide to Innovation and Reform. Boulder, CO: Westview Press (1978)
- Cano, J. (1999). "The Relationship Between Learning Style, Academic Major, and Academic Performance of College Students". Journal of Agricultural Education 40: 30. doi:10.5032/jae.1999.01030.
- Galotti, K. M. (1999). "Making a "major" real-life decision: College students choosing an academic major". Journal of Educational Psychology 91 (2): 379–387. doi:10.1037/0022-06126.96.36.1999.
- Simpson, J. C. (2003). "Mom matters: Maternal influence on the choice of academic major". Sex Roles 48 (9/10): 447–460. doi:10.1023/A:1023530612699.