Children's early knowledge and skills set the stage for later reading development. The present studies examined children's conceptual knowledge of reading prior to formal literacy instruction. Young children's knowledge about who is able to read books and what readers are reading when they read books has been studied primarily through interviews. However, conclusions from this research are limited by methodological concerns. In three experiments with a total of 105 U.S. preschoolers (ages 3 years, 1 month to 5 years, 5 months) we examined whether prereaders understand what part of a book is read, who can read, and who engages in reading. We created storybooks for Experiments 1 and 2, asking children questions about the print and what parts of a book an adult can read. In Experiment 3, we asked children questions about pictures of animals and adults looking at books. Although prereaders could generally locate letters and words in a book, they were still learning that it is this print, not the pictures, which a reader reads. Prereaders knew that adults but not animals have the ability to read, but many also indicated that engaging in the activity of reading does not require the ability to read. Children who cannot read are still in the process of learning that print is what a reader reads and that engaging in reading requires a special skill. Therefore, when formal literacy instruction begins, teachers should not overestimate the knowledge about print and reading that children have acquired from prior exposure to books.