Who they are
The eight gods are:
The number 8 comes partly from Timothy Leary and Robert Anton Wilson's eight-circuit model of consciousness. In the early days of the cult, the gods were often referred to as 'The gods of the eight circuits of consciousness'.
What they represent
The eight gods have been theorised to be: deities, angels, actual people on earth, symbols for something, empty representations of their own secrets, basic elements of the universe, and dimensions in themselves (which may be the ones making up the universe as it is today).
There is no hierarchy, but each of the gods is essential to the existence of the universe. Take away one of the gods, and the other seven cease to be possible. With them goes the whole of existence. For example, without Triangulon, mathematics, trigonometry and Euclidian geometry couldn't exist, so the whole universe would be impossible and undergo a Total Existence Failure. Without The Reality Fish, self-referentiality, hence consciousness, would be impossible, so the gods and all other conscious entities would die and the universe would again cease to be.
You could say they know each other in the way that chemistry knows maths exists, because chemistry's rules are often mathematical.