A students' union, student government, student senate, students' association, guild of students or government of student body is a student organization present in many colleges and universities, and has started appearing in some high schools. In higher education, the student union is often accorded its own building on the campus, dedicated to social and organizational activities of the membership. In the United States, student union many times only refers to a physical building owned by the university with the purpose to provide services for students without a governing body also referred to as a student activity center. Outside the United States this refers to a representative body.

Depending on the country: the purpose, assembly, method and implementation of the group might vary. Universally the purpose of students' union or student government is to represent fellow students in some fashion.

In some cases students' unions are run by students, independent of the educational facility. The purpose of these organizations is to represent students both within the institution and externally, including on local and national issues. Students' unions are also responsible for providing a variety of services to students. Depending on the organization's makeup students can get involved in the union by becoming active in a committee, by attending councils and general meetings, or by becoming an elected officer.

Undergraduate education is an education level taken in order to gain one's first tertiary degree (except for an associate's degree). Hence, in many subjects in many educational systems, undergraduate education is post-secondary education up to the level of a bachelor's degree, such as in the United States, where a university entry level is known as undergraduate while students of higher degrees are known as graduates. In some other educational systems and subjects, undergraduate education is post-secondary education up to the level of a master's degree, for example in some science courses in Britain and some medicine courses in Europe.

In India the Graduation system is classified into two Undergraduate (UG) and Postgraduate (PG) Systems. In India it takes three or four years to complete an "undergraduate" degree. The three year undergraduate programs are mostly in the fields of arts, commerce, science etc., and the four year programs are mostly in the fields of technology, engineering, pharmaceutical sciences, agriculture etc. However, for medicine, law and architecture, the period has been five years.