Personally identifiable information (PII) refers to data that can be used to identify, locate, or contact individuals or establishments, or reveal the characteristics or other details about them.

 

PII might consist of direct identifiers, such as the name, social security number or other information that is unique to an individual, or indirect identifiers. Indirect identifiers include uncommon race, ethnicity, extreme age, unusual occupation and other details. Combined with other information, such as state or county of residence, or information available through other sources such as professional directories, direct or indirect identifiers can disclose a respondent's identity.