When you create a group, you can choose 3 privacy settings: Public, Closed and Secret. The table below shows who can join these groups and what people can see about them. If you're an admin of a group, learn how to change the privacy settings of your group.
For the album by Pestilence, see Doctrine (album). Doctrine (from Latin: doctrina) is a codification of beliefs or a body of teachings or instructions, taught principles or positions, as the essence of teachings in a given branch of knowledge or belief system. The Greek analogue is the etymology of catechism.
The remainder of this article relies heavily on the short but detailed definition of the role and components of doctrine in the 2008 FM 3-0. As a military term, Army doctrine is defined as the fundamental principles by which the military forces or elements thereof guide their actions in support of national objectives. But doctrine is more than just principles.