A glossary of terms commonly used for stepper motors and stepper motor controllers.
DIR: Direction. You can set this HIGH or LOW to change the direction of rotation.
EN: Enable (turns on the motor).
PUL: Pulse. This is used to turn the motor shaft by a step. A step could be a shaft rotation at 1.8 degrees, 3.6 degrees, or another amount dependent on the model of motor.
CCW: Counter Clockwise.
CW: Clockwise.