As I argued in the previous chapter, drawings are a very flexible tool. We have used them for ages, and we have been able to adapt them to everchanging demands. As a consequence, graphics have never exhausted their utility as a medium for storing and transferring information. But just what kind of information is stored and transferred? How can graphic marks convey information? There is more than one answer to these questions, depending on how one approaches the problem. Different answers correspond to complementary attempts at understanding graphics, and I have devoted the next chapters to three such attempts. In this chapter, I investigate the nature of information as it is perceived or “picked up” by human perceptual activity. To understand how information may be stored in a drawing or picked up from it, I will elaborate on the theory of perceptual invariants, discussing empirical findings that pertain to this theory. Chapter 3 will then consider the issue of understanding how the information can be created and modified according to the relationships between different parts of a drawn scene. There my aim is to provide a critical assessment of the explanatory power of “context.” Finally, chapter 4 will discuss information from the point of view of the individual who draws, who is continuously engaged in selecting what needs to be preserved in the drawing and what can be neglected.