The diploma thesis Public sphere in networked society concerns about the relation of public sphere and cyberspace. Cyberspace is defined as new social institution, which is not embodied Habermasian normative ideal of critical public sphere, but in contrary it constitute new forms of inequalities and new forms of fragmentarization and commercialization. Explored are therefore also theories which critically deal with concept of public sphere and better describe the reality of cyberspace. The expansion of Cyberspace and horizontal communication network also relate with transformation of contentious politics. The thesis provides an overview of historical development of new action repertoire of contention - virtual sit-in. As an embodiment of all these societal shifts, which are seen as an elements of change in power balance, is presented Operation Payback orchestrated by hacktivist group Anonymous. Keywords Cyberspace, public sphere, hacktivism, action repertoires, repertoires of contention, virtual sit-in, electronic civil disobedience, Anonymous, Operation Payback

This master thesis explores the dynamics of information flows between the hacktivist group Guacamaya, media outlets and social media users. The study aims to understand the role of various social actors within the digital space such as media outlets, journalists, bots, and trolls, in shaping public opinion and the overall effectiveness of the group's communication activities. A netnographic methodology was employed to observe the journey and transformation of information as it travelled from the hacktivist group to journalists and eventually to social media users. Tweets were obtained purposefully, to build a media ecology with sentiments, topics and where different actors interact with the information and with each other, modifying and reinterpreting the purpose of Guacamaya. The theoretical framework draws on the concepts of technopolitics, hacktivism, information flows, the network society and gatekeeping. My findings show how the Internet is a contested territory where attention and power are disputed. They also provide evidence on the complexity of the communication process in the digital space as all interactions from all actors influence the information flow. The conclusions highlight the new media ecology environment and the multidisciplinary role of actors in the digital realm. Furthermore, they argue that hacktivism as counterpower involves more than technical skills for uncovering hidden information and demanding accountability, but also strategic reappropriation for reducing inequalities and promoting just and inclusive societies. Hopefully, this thesis contributes to understanding the potential of hacktivists groups to drive political and social change through the understanding of a new communication environment.