There was a time when many used to feel that it was fine to question Wikipedia’s accuracy. I never really felt this and can’t recall spotting an error – perhaps I know less than those critics.
I’m impressed by their glossary of musical terms – particularly the iPhone version, the alphabetical arrangement of which is elegant and user friendly. A nervous pupil, en route to a grade exam, could do worse than to look check up a few of these in the car. At home on PC it is a great resource – particularly when used in conjunction with Windows search function – Ctrl+F then the first few letters of the term in question.
Of course, when it comes to SQA concepts, there is no better site than LTS’ one – where audio illustrations of the concepts are included.