Biometric data are unique physiological or behavioural characteristics of a person that can be used for identification or authentication in an electronic system. In the world of marketing, they are increasingly being used to create personalised customer experiences or to ensure the security of transactions. Examples of biometric data include fingerprints, facial recognition, iris scans, voice recognition and even gait patterns. Each of these data categories provides a high degree of accuracy in identifying individuals and reduces the risk of identity theft or fraudulent activity.

However, biometric data is also the subject of data protection and ethics discussions. Unlike passwords or ID documents, biometric information cannot be changed if it is compromised. It is therefore essential for organisations to implement strict security protocols for the storage and handling of biometric data.

In the marketing context, biometric data can be used to gain a deeper understanding of customer behaviour and preferences. For example, by analysing facial expressions in real time, conclusions can be drawn about a customer's emotional response to a product or advertisement. This enables companies to adapt their marketing strategies and make them more targeted. However, data protection must always be guaranteed and the consent of the persons concerned must be obtained.