A memory institution is an organization maintaining a repository of public knowledge, a generic term used about institutions such as libraries, archives, heritage institutions, aquaria and arboreta, and zoological and botanical gardens, as well as providers of digital libraries and data aggregation services which serve as memories for given societies or mankind. Memory institutions serve the purpose of documenting, contextualizing, preserving and indexing elements of human culture and collective memory. These institutions allow and enable society to better understand themselves, their past, and how the past impacts their future. These repositories are ultimately preservers of communities, languages, cultures, customs, tribes, and individuality. Memory institutions are repositories of knowledge, while also being actors of the transitions of knowledge and memory to the community. These institutions ultimately remain some form of collective memory. Increasingly such institutions are considered as a part of a unified documentation and information science perspective.