The General Certificate of Education Advanced Level (commonly 'A level') is a qualification in the English school system. Students typically study 3-4 A level subjects from ages 16-19. Admission to A level courses depends on success in national school examinations at age 16.
A levels have for many years been considered the main indicator of suitability for university study (sometimes labelled as 'the gold standard'), and although other qualifications are considered, university entrance acquirements are often discussed in terms of the required A level grades (e.g. AAB, BBB, CDD) for different institutions and courses.