It involves writing directly onto a text such as slides, lecture-notes, or a photocopy/scan. This might be done digitally or on printed materials.
This method is ideal for efficiently engaging with content without extensive note-taking. You can even use it to take lecture notes, by writing your own notes directly onto a copy of the slides.
You can enhance your understanding by highlighting, underlining, and drawing on the slides of a text, making it easier to grasp key points and establish connections with the material.