Holy See
Although the Holy See is sometimes metonymically referred to as the "Vatican", the Vatican City State was distinctively established with the Lateran Treaty (1929) between the Holy See and Italy to ensure the temporal, diplomatic, and spiritual independence of the Papacy. As such, ambassadors are officially accredited to the Holy See and not the Vatican City State. Conversely, Papal nuncios to states and international organisations are recognised as representing the Holy See and the integrity of the Catholic Church along with its 1.3 billion members, not the Vatican City State, as prescribed also in the Canon law of the Catholic Church (1983). The "Holy See" thus refers to the See of Rome viewed as the central government of the Catholic Church. The Catholic Church, in turn, is the largest non-government provider of education and health care in the world, while the diplomatic status of the Holy See facilitates the access of its vast international network of charities.
Vaticanology
Vaticanology is term coined in the 20th century to describe the field of journalism and research studying and reporting about how the Holy See and the Roman Catholic Church operate. It is named after the Vatican City, the Holy See's sovereign territory enclaved with in Rome, Italy. Particular emphasis tend to be placed on the selection and appointment mechanisms by which the Church's leadership emerges.