Personally identifiable information (PII) refers to any data that can be used to identify an individual, either on its own or when combined with other information. This term is critical in the context of digital privacy rights, as it encompasses various types of data such as names, addresses, social security numbers, and even online identifiers that can compromise a person's privacy if mishandled or exposed. Understanding PII is essential in navigating issues around data protection, consent, and the ethical use of information in digital spaces.