When you do a search you can either search using “Search Archives” or “Show Timetable”. The “Search Archives” feature will search and attempt to rank the results based on the relevance of the history event being searched so that the articles that would be of interest to the user will be displayed first. Google takes into account the full text of each article, the publication in which the article appears, how often the underlying event has been referred to or described, in what manner and by whom. The “Show Timetable” will organize the articles by year and will flag certain key years related to the event being searched for easy viewing.
Some major publications that have been archived and are being searched are the New York Times, Wall Street Journal and Time magazine.