The General Certificate of Education (GCE) Advanced Level, or A Level, is a secondary school leaving qualification in the United Kingdom, offered as a main qualification in England, Wales, and Northern Ireland, as an alternative qualification in Scotland, and as an international school qualification worldwide.
The General Certificate of Education (GCE) Ordinary Level, also called the O-level or O level, is a subject-based academic qualification. Introduced in 1951 as a replacement for existing 16+ School Certificate (SC), the O-level would act as a pathway to the new, more in-depth and academically rigorous A-level (Advanced Level), in England, Wales and Northern Ireland. Later the complementary and more vocational Certificate of Secondary Education (CSE) was added to broaden the subjects available and offer qualifications in non academic subjects. The O-Level and CSE were replaced in the United Kingdom, in 1988, by the GCSE and later complementary IGCSE exams. The Scottish equivalent was the O-grade (replaced, following a separate process, by the Standard Grade). An O-level branded qualification is still awarded by Cambridge International Examinations in select locations.