Elective are classes outside the required core curriculum that students get to choose. You may find elective classes in subjects such as music, technology, computer programming, business, and more. Taking elective classes can give you a chance to explore your interests, or you may just want to take a credit that is less stressful for you.
Electives over and above the core curriculum, such as music, computer programming, or business can provide an interdisciplinary overlap with more traditional courses, creating a richer learning experience.
Colleges may have specific requirements outside the core courses, and electives are the place the student will want to take those if required. As a general rule, however, students should maintain a well-rounded and challenging schedule.