The aim of this thesis was to determine current legal status as to whether it is allowed to share or upload images on social media without asking for permission. The thesis has examined whether an image shared on social media can be a personal data, legally speaking. The legislation about this subject is spread in different laws, which make it difficult to determine what is allowed to do and not. Furthermore, a survey on Facebook investigated the extent to which people share photos on Facebook without asking the people in the photo. The result showed that a lot of people shares pictures without asking permission if they know the person in the photo. If the participants did not know the person, they did not share the photo to the same extent. The participant also answered the question how well they thought they knew about the legislation regarding personal data, surveillance and crime. Half of the participant estimated that they knew about the legislation.