This unit introduces the specialist computing area known as Human Computer Interaction (or HCI for short). One aim of the unit is to give you a clear understanding of what practitioners and researchers in this field know and do. Importantly, too, the unit will try to motivate you to see that HCI is a vital component of successful systems development by giving success stories where the user was considered in the design and failures where the users were overlooked. The unit will also outline the other units in the course and give full details of the assessment scheme used.