L: Start clicking to continuously draw lines. (No need to drag/hold the mouse key)

C: Draw a circle by selecting the center and radius. (Again, No need to drag/hold the mouse key).

R: Draw a rectange by selecting two corners. (Needless to say, there is no need to drag/hold the mouse key)

U: Undo last action.

Y: Redo the undone action.

G: Activate/deactivate grid mode. With gridmode:on, cursur sticks to the grid.

M: Activate/deactivate magnet mode. With magnetmode:on, curser sticks to the nearest point (if availabe).

E: Export all points.

P: Start clicking to draw a polyline. (There is no need to...).

S: Start clicking to draw a spline. (Like others, no need to drag)

B: Draw continues quadratic bezier curves.

X: By holding X button, you can draw a perfect horizontal line (line & polyline only)

Z: By holding Z button, you can draw a perfect vertical line (line & polyline only)