There are two major alignments; order and chaos; and a non-alignment, which is neutral. A player character starts the game with neutral (0) as alignment.
ORDER NEUTRAL CHAOS
6 5 4 3 2 1 0 1 2 3 4 5 6
Alignment changes over time, as your deeds affect how you are aligned with the rest of the world. As you work for others such as factions, lords, employers, etc. and do their bidding, your alignment slides toward theirs.
NPC Alignment
For non-player characters (NPC), you can use a simpler alignment such as below: