NLP & Language · intermediate · concept 139 of 311 · Updated Nov 4, 2026

❓Question Answering

Question answering systems return a direct answer rather than a list of documents. Older systems extracted a span of text from a passage; modern ones retrieve sources and have a language model write the answer. The core risk is a fluent wrong answer, so a good system shows where the answer came from and can say it does not know.