PII or Personal Identifiable Information is any data that can be used to clearly identify an individual. Some examples are, national insurance numbers in the UK, your mailing address, email address and phone numbers, have been traditionally been considered personal information but as technology has improved, the scope of PII has grown considerably to now include IP addresses, login ID details, social media posts and digital images, as well as geolocation, behavioural and biometric data, which is now all considered to be PII.