User interactionThere is no game without interaction with the user. The standard way of doing this in GameMaker is to put actions in mouse or keyboard events. But sometimes you need more control. From within a piece of code you can check whether certain keys on the keyboard are pressed and you can check for the position of the mouse and whether its buttons are pressed. Normally you check these aspects in the step event of some controller object and take action accordingly.
Information on user interaction can be found in the following pages: