There is no degree in Freemasonry higher than that of Master Mason, the Third Degree. There are, however, a number of organisations that require being a Master Mason as a prerequisite for membership. These bodies have no authority over the Craft. These orders or degrees may be described as additional or appendant, and often provide a further perspective on some of the allegorical, moral and philosophical content of Freemasonry.
Appendant bodies are administered separately from Craft Grand Lodges but are styled Masonic since every member must be a Mason. However, Craft Masonic jurisdictions vary in their relationships with such bodies, if a relationship exists at all. The Articles of Union of the “Modern” and “Antient” craft Grand Lodges (into UGLE in 1813) limited recognition to certain degrees, such as the Royal Arch and the “chivalric degrees”, but there were and are many other degrees that have been worked since before the Union. Some bodies are not universally considered to be appendant bodies, but rather separate organisations that happen to require prior Masonic affiliation for membership. Some of these organisations have additional requirements, such as religious adherence (e.g., requiring members to profess Trinitarian Christian beliefs) or membership of other bodies.
Quite apart from these, there are organisations that are often thought of as being related to Freemasonry, but which have no formal or informal connections with Freemasonry. These include such organisations as the Orange Order, which originated in Ireland, the Knights of Pythias, or the Independent Order of Odd Fellows.