## 4 Case Studies
### Re-Contextualizing Digital CH: The Legacy of Social Media Data  
In this case study, we reflect on preliminary work concerning the digital legacy of social media data. We argue that the meaning of the term _digital CH_ as we know it today is twofold. One relates to the tools and interfaces applied to preserve and experience analog CH [119; 120] as presented and discussed in the previous case studies. In contrast, the second results from the increasing usage of digital services and the creation of online identities [121; 122], which, in our argumentation, create personal digital CH. Elaborating on our argumentation, users spend an average of 6.4 h per day online globally [123] in different community platforms and other activities. Thus, the digital realm is becoming an increasing part of our contemporary and future CH, inducing new social norms, values, behaviors, and CH preservation requirements. Furthermore, technology has changed how we communicate and experience our world, moving many conversations, rituals, or habits into the digital realm. Social media platforms further enable us to create one or more digital identities that can survive their creator [124] and add value on individual, social, cultural, and economic levels [125]. The breadth of possibilities for curating digital identities enables users to craft them independently from their analog lives while all along remaining bound to similar needs for social acceptance and belonging [126]. Beyond the individual, companies, institutions, and governments also maintain online identities to quickly reach a broad audience via different communication channels and platforms. This shift also relates to increasing communication and identity representation based on images and videos [127]. With all these new digital data, identities, and communities, we create digital cultures that shape the basis of dynamic, volatile, and globally connected CH. Related to this development, new questions arise regarding data ownership and agency. Those questions relate to the level of individual user inclusion and the understandability of the massive amount of data. The situation aggravates considering end-of-life scenarios when the data agency has to be handed over to an \"heir\" [128]. While many regulate their obituary through a testament, our digital data often remains untouched, lacking clarification on how to proceed. The reasons for treating the digital and the analog legacies differently are based on multiple reasons, among others, the lack of transparency of digital data, a data overload [129], and users' neglecting attitude to engage in the topic. The latter can be partially explained by the post-mortem privacy paradox [130] that describes the discrepancy between users' attitudes versus their actual behaviors regarding data preparation before death [130; 131]. The paradox adds to the privacy paradox [132; 133] and describes how users' action opposes their attitude by willingly handing over digital data for further usage, application, or access by third parties but consider data privacy very relevant. In most cases, data handling by companies and involved third parties stays non-transparent, leading to companies having knowledge and perspectives of an individual user other than the users themselves. At the same time, users have the \"_right to be forgotten_\" [134; 135] and decide how and by whom their data will be used after their death. However, digital data, such as our social media images, scale very quickly and immensely compared to the uniqueness and stability of built heritage or physical artifacts. This makes digital data nontransparent and hard to maintain [129]. HCI research addresses the challenge by exploring different tools and approaches that empower, motivate, and enable users to handle their data transparently and guard their agency and ownership.