A master's degree typically takes between one and three years to earn, and requires that a student complete between 30 and 50 credit hours of study. In some fields, a student must choose between becoming a Master of Arts (M.A.) or Master of Science (M.S.). The investment of time, money and effort is much the same, but the focus is different. Generally, M.S. degrees are more specialized and technical. Some fields offer only one or the other; you can't undertake a Master of Science in English Literature or a Master of Arts in Chemistry.

Different Purposes and Prerequisites

A Master of Arts program takes a broad-spectrum approach to a particular discipline, deepening students' understanding in a field they may or may not have specialized in as undergraduates. A Master of Science degree focuses more on hard-science aspects of a discipline and technical skills, and students generally need to hold a bachelor's in that specific field to be considered for admission. Some studies in the arts and humanities lead only to an M.A. (though the program may be part of or lead to doctoral studies) while some in the "hard" sciences and mathematics award only the M.S.

Different Teaching Methods

To earn an M.S., a student does substantial field or laboratory work and writes and defends a thesis. In any field, an M.S. program focuses more on the technical and hands-on aspects of practice, while an M.A. program focuses on theoretical understanding. M.A. studies include seminar-style classes and advanced level reading and writing within a discipline, and may or may not require a formal thesis component.

Different Outcomes -- Sometimes

The choice of a master's degree program -- or track within a program -- depends on the specific career track you wish to pursue within your field. Both types of master's degree programs can lead to certification in a number of professional fields, which might range from teaching and counseling to business and applied-science fields. Whether programs that meet your goals are packaged as Master of Science or Master of Arts programs may vary not only by field but by institution.

The University of Western Michigan, for example, offers only an M.A. in Counseling; students at the State University of New York at Buffalo earn an M.S. According to licensed counselors -- like Dr. Barbara LoFrisco, who writes the MastersinCounseling.org blog -- both types of degrees can lead to professional licensure as a counselor, though M.A. candidates typically go on to pursue research and teaching in the field through advancement to doctoral programs.

Although the European Union has chosen to adopt a standardized definition of the distinction between an M.S. and an M.A., in the United States, the differences are somewhat less clear-cut.

Professional Master's Degree Programs

Both M.A. and M.S. degrees are considered "academic" master's degree programs, focused on either generalized or specific research and theory, which, in many cases, may lead to doctoral studies. Professional or "terminal" master's degrees are designed to be complete in themselves and equip graduates for a specific professional role. These programs tend to focus on applying hands-on skills and meeting established professional requirements. They often lead to degrees named according to the professional field, such as Master of Business Administration, Master of Social Work or Master of Urban Planning.