O Level is a British educational qualification that is usually taken by students at the age of 16. This qualification is equivalent to the General Certificate of Secondary Education (GCSE) in the UK. Some synonyms for the term O level can be senior Cambridge, GCE O Level, and ordinary level. These qualifications are seen as significant achievements, marking the end of the secondary education and preparing students for higher education. O level is a standardized exam that tests the student's ability in various subjects such as English, Mathematics, Science, and Humanities. The term O level is linked with the British education system and has been replaced by GCSE in most cases, but O level is still used in some countries worldwide.