Tools for Achieving Usable Ex Post Transparency: A Survey <s> a: EXPLICIT DATA <s> This paper provides a short survey on transparency tools for privacy purposes. It defines the term transparency tools, argues why they are important and gives examples for transparency tools. A classification of transparency tools is suggested and some example tools are analyzed with the help of the classification. <s> BIB001 </s> Tools for Achieving Usable Ex Post Transparency: A Survey <s> a: EXPLICIT DATA <s> Transparency is a basic privacy principle and social trust factor. However, in the age of cloud computing and big data, providing transparency becomes increasingly a challenge. <s> BIB002
As far as different kinds of data are concerned, 'explicitly disclosed personal data' BIB002 refer to data wilfully and knowingly provided by a data subject, and are stored and processed by the data controller with the data subject's consent. Such data could, for example, be entered via a sign up registration form for an online service or subsequently be provided by customising a user's online profile. b: IMPLICIT DATA 'Implicitly disclosed personal data' BIB002 refers to personal data that are being processed or stored by a data processor without the explicit consent of the data subject. The data subject may or may not be aware of the fact that such data are being collected. The IP address of the user's communication device or the time of an online transaction are examples of implicitly disclosed personal data. Implicit data relate to what Hedbom BIB001 refers to as 'extended information,' denoting data that are not legally required to warrant the respective service but that are being collected nevertheless. Many of the reviewed TETs that deal with location-based services served the purpose of reviewing queries of the user's disclosed location or availability, and provide temporal information about when such queries were issued. These data are not treated as implicit data in Table 2 because they are related to dates of queries rather than the target person's personal data. Conversely, the user's location is considered explicitly to be disclosed data, as long as the originator knowingly uses the service to share her location in the first place. In the case of TETs that monitor the unintentional leakage of the user's location, however, such data are considered implicitly disclosed data.