Avidyā, ignorance or nescience, is not a lack of information but a fundamental misperception: taking the self to be the body and mind, and the world of separate things to be ultimately real. In Advaita Vedānta it is removed only by knowledge of the self as Brahman. In Buddhism, ignorance of the Four Noble Truths is the first link in the chain of dependent origination.
Avidyā
Ignorance: the beginningless misunderstanding of one’s true nature that, in Indian thought, binds the self to suffering.
Also: Avidya, nescience