The Catholic Encyclopedia, also referred to today as the Old Catholic Encyclopedia and the Original Catholic Encyclopedia was published in the United States. The first volume appeared in March 1907 and it was completed in April 1914. It was designed "to give its readers full and authoritative information on the entire cycle of Catholic interests, action and doctrine.
It also offers in-depth portrayals of historical and philosophical ideas, persons and events, from the Roman Catholic point of view. On issues that divide Catholicism from other churches and Protestant ecclesiastic communities, the text consistently presents matters from the Catholic point of view. Since the encyclopedia was first undertaken in 1913 and has never been updated, many of its entries are out of date either with respect to the wider culture or to the Catholic ecclesiastical world. In particular it predates the creation of the Vatican City State and the Second Vatican Council (1962–1965), which introduced many significant changes in Catholic practice. (Adapted from Catholic Answers Web Site).
These Dictionaries and Encyclopedias can be quite useful for beginning research about Church History or Catholicism, or for clarifying terms and gaining background knowledge. Many entries include bibliographies.