Personal data, more commonly referred to as personal data", is any information relating to an identified or identifiable natural person.
▶ Information can be of any kind: a text, an image, computer code, speech, whatever the medium.
▶ Information concerns one person and one person only, not a group of people. The information must not only refer to the person but must be attributed to him or her. For example, a comment may not mention the name of a person but concern that person alone. This is personal data.
a natural person
▶ This means that it concerns a human being and not an animal, a company or an association. The right to protection of personal data is one of the fundamental human rights ("human rights").
identified or identifiable.
▶ The person must be identifiable, i.e. directly when the information relates directly to the person (e.g. first name and surname) or indirectly. This is the case when the information, when combined with other information, makes it possible to identify the person.
This definition can be found in Article 4 of the GDPR (the General Data Protection Regulation), as well as in Article 2 of the Council of Europe's Convention 108. This definition seems fairly unanimous.
Right of access
Although it is easy to talk about personal data rather than personal data, this difference is important because it underlines the non-possessive nature of data. Information is only attributed a personal character. Basic information can be given this character over time.
For example: "a red car" is harmless, but in a car park where the only red car is the boss's, the information is given a personal character in the context of the car park. However, the information "the red car" does not belong to him. He only has rights over the data that concerns him. As an individual, he has the right to know what concerns him in order to control his private life.
This translates into a legal concept highlighted by the German Constitutional Court in the 1970s, informational self-determination.
This protects the companies that own this information and allows the people concerned to have a say in what concerns them.