The digital transformation of our societies and in particular information and communication technologies have revolutionized how we generate, communicate, and acquire information. Collective memory as a core and unifying force in our societies has not been an exception among many societal concepts which have been revolutionized through digital transformation. In this chapter, we have distinguished between "the digitalized collective memory" and "collective memory in the digital age". In addition to discussing these two main concepts, we discuss how digital tools and trace data can open doorways into the study of collective memory that is formed inside and outside of the digital space.