Maya is the most famous Hindu idea in the West and the most consistently misdescribed. Shankara is not saying the world is a hallucination — he is saying it has a lower grade of reality, the way a dream is real while you are in it, and that Brahman alone is real without qualification. The rope-and-snake analogy is his: you did not see nothing, you saw something and misidentified it. Ramanuja's attack is that this makes the scriptures, the teacher, and Shankara himself unreal, which is self-defeating; Madhva's is blunter still. What almost nobody in the tradition holds is the popular version in which the world does not matter — Advaita renunciates run hospitals and schools, and Shankara himself is said to have spent his short life walking the length of India arguing. The scope here is contested for a reason: presenting Advaita as Hinduism's position is the single most common error in English writing about it, and it is largely Vivekananda's doing.