GCSE English exam boards
The four boards assess the same two subjects and weight them differently. Which one you sit changes what your answers are marked against, which is why Marked asks for it before it marks anything.
AQA
AQA is the most-sat English specification in England. Both subjects run across two papers, and the writing tasks carry more marks than most students give them time.
Edexcel (Pearson)
Edexcel's papers are closer in shape to AQA's than most students expect, with two differences that catch people out: the picture prompt on Language Paper 1, and questions printed in lettered parts.
OCR
OCR builds its Language components around themes rather than text types, and splits several Literature questions into two equally weighted halves.
WJEC and Eduqas
WJEC is the only board here with tiered Literature papers, and its Language units mix short structured questions in with the longer responses.
Not sure which board you are on?
It is printed on your exam timetable and on the front of any past paper your school has given you. If you genuinely cannot find it, ask your English teacher rather than guessing: marking an answer against the wrong board produces a grade that looks reasonable and is not.
You can change your board at any time in your account settings, and it takes effect on the next answer you submit.
Put one answer through it
The free tier needs no card. Paste an answer you have already written and see the grade, the mark band and the reasoning behind both.