Human-computer interaction (HCI) is a multidisciplinary field that involves the study of computer design technology. It also studies the relationship of the users with computers. HCI intersects with multiple domains such as computer science, cognitive science and human-factors engineering. End-user computing satisfaction or user satisfaction is a key aspect of HCI. Its scope expanded with the emergence of technologies such as Internet and smartphone. HCI focuses on generic and individual user behavior. It also incorporates social and organizational computing. It caters the spectrum of human experiences and activities including accessibility for the elderly, and for the cognitively and physically impaired. The applications of HCI range from games, learning and education, commerce, health and medical applications, to emergency planning and response. This book outlines the new paradigms in the field of human-computer interaction in detail. It is appropriate for students seeking detailed information in this area as well as for experts.