It can be his full name, address, email, birth date, or sets of anonymous data that make it possible to identify him. The definition of PII is still debated and keeps evolving over time. For instance, IP addresses, which characterise the connection of a device to a network, have only been considered as PII since 2016.
PII (Personally Identifiable Information)
Personally Identifiable Information (PII) are specific information that allow an individual to be identified in a direct or indirect way.