Human-Computer Interaction (HCI)
There is currently no agreed upon definition of the range of topics which form the area of human-computer interaction. HCI in turn draws upon a number of different fields and is a discipline concerned with the design, evaluation and implementation of interactive computing systems for human use with the study of major phenomena surrounding them. Here is a working definition (more can be found at following site).
Professional practitioners in HCI are usually designers concerned with the practical application of design methodologies to real-world problems. Their work often revolves around designing graphical user interfaces and web interfaces. Researchers in HCI are interested in developing new design methodologies, experimenting with new hardware devices, prototyping new software systems, exploring new paradigms for interaction, and developing models and theories.