The aim of the present chapter is to draw a brief review of the main empirical evidence, which is available either in the literature or as results from authors’ recent work, about the effects of literacy on language and cognition. Concerning language, the evidence is reviewed separately for metalinguistic and linguistic abilities. Brain differences are also evoked. Concerning cognition, we examine, in this order, visual processes, memory, semantic knowledge, reasoning, and executive processes. Finally, we draw the theoretical implications of the reviewed findings.