Short answers, pulled from the story.
Freemasonry is a set of fraternal groups that trace their origins to medieval guilds of stonemasons. It is considered the oldest existing secular fraternal organisation, with documents and traditions dating back to the 14th century. Its members are known as Free-Masons, Freemasons, or Masons.
The three degrees of Freemasonry are Entered Apprentice, Fellow Craft, and Master Mason, inherited from medieval craft guilds. A candidate is progressively initiated, passed, and raised through these degrees in separate ceremonies. At each degree he is entrusted with grips, signs, and words to signify which degrees he has taken.
The first Grand Lodge was founded on St John's Day, the 24th of June 1717, when four existing London Lodges met for a joint dinner. It was first called the Grand Lodge of London and Westminster and later the Grand Lodge of England. The Premiere Grand Lodge and the rival Antient Grand Lodge re-united on the 27th of December 1813 to form the United Grand Lodge of England.
Estimates of worldwide Freemasonry membership in the early 21st century ranged from about two million to more than six million. The largest single jurisdiction is the United Grand Lodge of England, with a combined membership estimated at 175,000. In the United States, 51 Grand Lodges hold a total membership of around 875,000.
The Catholic Church opposes Freemasonry on the allegation that it teaches a naturalistic deistic religion in conflict with Church doctrine, along with the practice of blood oaths. More than 600 Papal pronouncements have been issued against Freemasonry, beginning with Pope Clement XII's In eminenti apostolatus in 1738. In 2023, Pope Francis reaffirmed the ban on Catholics becoming Freemasons.
Prince Hall Freemasonry exists because early American lodges refused to admit African Americans. In 1775, Prince Hall and 14 other African American men were initiated into a British military lodge under a warrant from the Grand Lodge of Ireland, and in 1784 they formed African Lodge, Number 459. Today most US Grand Lodges recognise their Prince Hall counterparts.
James Anderson's first printed constitutions of the 1720s specifically excluded women, but women's and mixed Masonic bodies later developed. Maria Deraismes was initiated in 1882 and, with Georges Martin, started a mixed masonic lodge. In 1999 the United Grand Lodge of England recognised The Order of Women Freemasons and The Honourable Fraternity of Ancient Freemasons as regular in all but the participants.