This category holds the organised initiatory bodies of the esoteric world: Freemasonry, the Rosicrucians, the Hermetic Order of the Golden Dawn, the Ordo Templi Orientis and others. What defines them is form: membership admitted through initiation, teaching structured in degrees, and often a measure of secrecy about their rites and lore.
Each entry records, so far as the record allows, when and where the body was founded, what it taught or practised, how it was organised, and its documented history, keeping to what can be established.
Some are held here on other grounds, and it is better to say so than to let the definition stretch to cover them. The Knights Templar were a medieval Catholic military order, founded about 1119 and dissolved by papal bull in 1312, with no graded esoteric curriculum of any kind; they are here because Freemasonry and its offshoots later claimed descent from them, a claim the record does not support and which the entry treats as legend rather than history. Skull and Bones is a senior society founded at Yale in 1832: closed and initiatory, and nothing more than that. Neither has a better home in the atlas, and both are kept here with the mismatch stated rather than hidden.