There are many ways of practicing magic, with each general category referred to as its own magical tradition. All of them have the same general limitations and range of effects, but the way that one performs a spell can vary significantly between traditions.

Your choice of magical tradition is purely a roleplaying one — you can achieve the same mechanical effects with your spells and rituals regardless of what tradition you employ. Choose the tradition that you think that you’d enjoy the practice of and that makes sense for your character to use.