Character class rules outline all of the different class options for a character. A character’s ‘class’ is, essence, what a character would say when asked ‘what do you want to be when you grow up?’ If you are just creating a character, this is the place to start.
If you are more interested in what a character believes rather than what they do, alignment is the place to look. Alignment is determined partially by race.
Political Alignments, like being a Democrat or Republican, are exclusively human in this world, but a human can decide to be whatever political alignment they like.
Elemental Alignments belong to all of the other races, Elves, Short Ones and Monsters. A non-human’s alignment is determined totally by their race. Certain classical elements like fire and water and ice, have certain characteristics that a given race will adhere to.