History is the study of the past. Events occurring before the invention of writing systems are considered prehistory. "History" is an umbrella term that relates to past events as well as the memory, discovery, collection, organization, presentation, and interpretation of information about these events. Scholars who focus on history are called historians. The historian's role is to place the past in context, using sources from moments and events, and filling in the gaps to the best of their ability. Written documents are not the only sources historians use to develop their understanding of the past. They also use material objects, oral accounts, ecological markers, art, and artifacts as historical sources. History also includes the academic discipline which uses narrative to describe, examine, question, and analyze a sequence of past events, investigate the patterns of cause and effect that are related to them.
The network was originally focused on history-based documentaries and historical fiction series though, during the late 2000s, History would drift into reality television programming. In addition to this change in format, the network is also criticized by many scientists, historians, and skeptics for broadcasting pseudodocumentaries and unsubstantiated, sensational investigative programming.