Throw 50 gamers in a room and you'll get at least 100 different visions of what alignment is supposed to mean in a game. Codes of conduct, universal standards, alignment-linked classes, whether the game should have alignment at all, arguments about the true nature of good and evil, law and chaos, comparisons to real-world politics and religion, inevitable invocations of Godwin's law and the ethical dilemma of redemptive violence as a trope, whether orc babies are born evil, and a million other things have plagued message boards and discussion groups as long as gaming has been a thing.
As Corefinder is, at its heart, a refinement of the Pathfinder RPG, it does retain alignment, and especially in Corefinder Fantasy there will be more specific game rules relevant to it, in particular as it touches on the planes of existence, supernatural creatures and abilities, and the like. In Corefinder Basic, it remains what it always has been best at being: a simple shorthand that describes your character's general morals and ethics in the broadest possible strokes.
Alignment: Alignment represents a general moral and ethical outlook on the world and the creatures in it. Lawful creatures favor order, systematic thinking, and community while chaotic creatures favor freedom, spontaneity, and individuality. Good creatures favor generosity, selflessness, and sacrifice to help others while evil creatures favor selfishness, cruelty, and exerting power over others no matter the cost. Neutral characters on either axis tend to avoid either extreme, though some do so out of ambivalence or dispassionate detachment while others strive to maintain a dynamic balance in the world around them as the best way to create opportunities for themselves and others.
Alignment is descriptive rather than proscriptive, and other than for supernatural creatures that are the literal embodiments of their alignment, it does not compel any particular course of action or constrain the choices of the players.
Alignments are typically abbreviated with the first letter of each component, with the law-chaos element followed by the good-evil element. Hence, LG would represent Lawful Good and CN Chaotic Neutral. Creatures that are neutral in both regards, sometimes called “true neutral,” are simply abbreviated with an N.
Mindless creatures generally have no alignment unless imbued with an alignment essence by some supernatural means, such as a necromantic ritual to raise the dead. Unaligned creatures are abbreviated with a U. Unaligned creatures are immune to alignment-based effects unless otherwise stated.