They focus mainly on academic subjects in contrast to vocational qualifications such as BTECs and NVQs, which are more practical.
Since they’re highly valued by both employers and universities, they can be very useful for students looking to keep doors open for further education and careers. However, the small number of subjects a student studies at A-Level does mean there is some specialisation.
University offers are typically made as grade requirements for 3 A-Levels, so it is not actually necessary to take more than this (though some may require an additional AS level).
There are currently more than 40 A-Level subjects to choose from. Some of these are continuations of subjects offered at GCSE, while some are entirely new.