The Pen Tool allows the user to add freehand notes and drawings to the Graphics View. This makes the Pen Tool particularly useful when using GeoGebra for presentations or with multimedia interactive whiteboards. To add a freehand note onto a region of the Graphics View, activate the tool and draw on your touch screen or with your mouse by holding the left mouse button
GeoGebra stores the notes you traced in the Graphic View as a PenStroke (assigning the name stroke to it). Therefore you can use several operations on them (e.g. move, rotate, recflect,...).
The default colour of the pen is black, but you can change the pen properties (colour, style, and thickness) using the Styling Bar.
To erase a portion of your notes created in the Graphics View with the Pen Tool, press and hold the right mouse button while moving it on the notes you want to delete. Release the mouse button to finish.
In order to delete the stroke you previously created, erase it totally in the Graphics View, or use the Context Menu of the object, or just delete the corresponding item in Algebra View.