The Trimester System is an academic calendar divided into three terms, each lasting about 12 to 14 weeks. This system allows students to complete courses more quickly than in a traditional semester system, which typically has two longer terms. Many colleges and universities use this approach to offer a wider variety of classes and to accommodate different learning styles. In a trimester system, students often have the option to take classes during the summer, providing even more flexibility. This structure can help students graduate sooner or explore additional subjects, making it a popular choice for institutions like Harvard University and Stanford University.