Personal data is defined as any piece of information relating to an individual which could identify that individual.
More obvious examples include names, addresses, and contact details, however it can also include images of people, passwords, ip addresses and much more.
Further, some types of data a classed as 'special category' - these are types of data considered to be more sensitive, such as racial or ethnic origin, political opinions and biometric data, among others. The processing of special catewgory data has more stringent conditions associated.