Music is a crucial element of everyday life. People spend hours listening to it and billions of dollars buying it. Yet despite the pervasiveness of music, mainstream social-personality psychology has hardly given any attention to this universal social phenomenon. Why is music important to people? What role does music play in everyday life? This article reviews research in fields outside mainstream psychology concerned with the social and psychological factors that influence how people experience and use music in their daily lives. The research in this area shows that music can have considerable effects on cognition, emotion, and behavior. It also indicates that people use music to serve various functions, from emotion regulation to self-expression to social bonding. Research in this emerging field reveals how social-personality psychology can inform our understanding of music, and in doing so it highlights the real-world relevance of mainstream theory and research.