String height is the distance between the bottom of the string and the top of the fret.

String height affects playability and making changes to the height is known as "setting the action."

Height is adjusted with the set screws in the saddles attached to the bridge.

This is a simple overview of the process. More in-depth teaching is done in the full course, Build Your Own Custom Guitar.

If you like the quality of the videos and teaching done in this course, consider purchasing tuition and gaining access to the entire guitar building universe, available right now.