An academic semester is a division of the academic year used by educational institutions to organize courses and schedules. Typically, a semester lasts around 15 to 18 weeks, during which students attend classes, complete assignments, and take exams. Most colleges and universities operate on a two-semester system, with the fall and spring semesters being the most common. Some institutions also offer a summer semester, which is shorter and often focused on intensive courses. Each semester usually begins with a registration period, followed by classes, midterms, and finals. This structure helps students manage their coursework and progress toward their academic goals.