For a modern user, a calendar is usually a reference table that lists all the days of the year in sequential order, dividing them into months and weeks, and highlighting weekends and holidays with a special color. People of the 18th century gave the calendar similar definitions, but its functions were much broader: the calendar became a desk book, fulfilled the functions of a notebook, an individual for each family home directory — for this purpose in the copies, even at the stage of conclusion in the cover or binding, blank sheets were bound to keep family and household records. Throughout most of the 18th century, the Imperial Academy of Sciences in St Petersburg had the exclusive right to issue calendars, and the calendars, along with other academic publications, were subject to state and church control, as they contained current information about persons serving at the court and about the highest Russian officialdom. The Russian State Library as part of the collection of the Research Department of Rare Books (Museum of Books) holds a representative collection of calendars and monthbooks of the 18th century, which makes it possible to get acquainted with the repertoire of this type of publications. The present study examines the subjects and readers’ address of calendars or monthbooks of the 18th century, reveals the content of the “Calendar or Monthbook for the summer from the Nativity of Christ...”, court, historical, geographical, economic, travel, church, “fortune-telling” calendars on the example of copies from the collection of the Book Museum.The calendar as a type of publishing reacted sensitively to the changes that took place in society and in the book business in different historical periods, tried to record the information that seemed important to contemporaries, helped owners to structure their lives and the lives of their families, their homes and households. Calendars had their readers and admirers. It is in the calendar that one finds information that has not passed the test of time, but is so necessary to reconstruct the history of everyday life of a particular era.