Personally Identifiable Information (PII)
Personally identifiable information (PII) is any data that can identify a specific individual on its own or combined with other data, such as name, email address, phone number, or government ID. Handling PII responsibly is central to privacy law and data security.
PII sits at the core of first-party data because identity fields are what let you connect behavioral, transactional, and support records to a real person.
Because it is sensitive, PII should be collected with consent, minimized to what you need, protected with access controls and encryption, and governed with clear retention rules. Many systems hash or tokenize PII so records can be matched without exposing raw identifiers.
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