Human-Computer Interaction

Human-Computer Interaction  is a study of the design, evaluation, implementation and use of interactive systems.  It mainly focused on the interfaces between people (users) and computers. HCI has since expanded to cover almost all forms of information technology design.
The Association for Computing Machinery (ACM) defines Human-Computer Interaction as "a discipline concerned with the design, evaluation and implementation of interactive computing systems for human use and with the study of major phenomena surrounding them".