With the pervasiveness of sensors, Internet-enabled devices, mobile phones, Internet applications and services, and wireless communication, a new field of social and community intelligence (SCI) has emerged quite quickly. SCI aims to reveal individual and group behaviors, social interactions, and community dynamics by mining the digital traces that people leave while interacting with Web applications, static infrastructure, and mobile and wearable devices. Author Daqing Zhang and colleagues provide an introduction to this field and highlight the various technologies.