# Does Nightfall require data to be already tagged? No, Nightfall doesn’t require data to be pre-tagged. Nightfall uses machine learning to detect 100+ types of sensitive data out of the box, without prior tuning or tagging required. This includes forms of PII, PHI, PCI, and other sensitive content – for example, emails, social security numbers, etc. Our detectors leverage context surrounding a specific token to properly identify and classify it, which dramatically improves accuracy over traditional rules-based approaches to DLP. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://help.nightfall.ai/faqs/data_tagging.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.