In stick fighting there are many systems for explaining the attacking angles. These differences sometimes reflect environmental, combative and/or philosophical differences. In the end, they are all correct. An angle is angle is an angle. Don't overthink it.
Below is my system of 17 angles. These are loosely based off of the Inosanto-Lacoste system of Kali. Over the years I feel that this is an easy base system of angles to learn and then you can branch off to various other systems and easily adapt to their angles.
PLEASE NOTE: one of the biggest differences in mine is that the angle represents the path not a destination to a specific target. Thus a downward diagonal angle from right to left is an "angle 1" whether it hits the temple, the elbow or the knee.