Freemasonry is a fraternal organization formed in the 1700s in England. They various lodges around the world are affiliated with each other (for the most part) an they have a shared moral and metaphysical ideals andin most of its branchesby a constitutional declaration of belief in a Supreme Being.
My grandfather was really into Freemasonry, but I was too young to really learn much about it. My information comes from later in life.
There is a lot of mythology about the Masons because during the height of the British Empire and the formations of the American colonies, a lot of powerful politicians were members. So they are ripe for lots of conspiracy theories.
These days, most people join the Masons for the same reason they would join other fraternal organizations; mostly for the social and business networking advantages.
They have to progress through various "degrees" of membership status by studying bizzarre and arcane Masonic philosophy. There are still a lot of secret ceremonies to promote Masons through the ranks, but I think they like to downplay that these days.
Some would classify their basic theology as "Deist", but these days they are even less dogmatic than that. They just refer to the Creator as The Great Architect.
I went to public "installations" when some people were promoted when I was a kid, and loved the pageantry and ceremony what with the people wearing capes and swords and stuff. I mostly remember the potluck suppers and the Christmas parties, though.
Oh yeah, they have a
cool logo which has a compass (the kind that draws circles) and the square that form the same symbol that was talked about in The Davinci Code. Ironically, they didn't mention that in the movie.
They would like you to think the organization is thousands of years old and holds important secret metaphysical secrets. The rumor is that Alexander The Great was a Freemason, but that came from Kipling's story The Man Who Would Be King. Its not really that old.
I think its still only open to men, but there is a women's organization called Daughters of The Eastern Star. Teenage boys join The DeMolays, and girls join Rainbow Girls.
Have I put you to sleep yet? I have a tendency to do that.