Human Computer Interaction (HCI) is about people interacting with technology. It looks at how technology is designed, and how it should be designed to make it easy and interesting for people to use.
Computers are all around us - so much that we are sometimes not even aware of them. You probably use a computer at work, perhaps to write documents, to find information in databases, and the Internet to send mail. At home you may decide to set the VCR to tape your favourite show next week, or you may set the oven to ensure your dinner is ready the moment you get home. We use computers everywhere, every day.
It's said that computers make life easier, but do you really know how to correctly set your VCR, or do the kids do it? Do you ever ask your colleagues for help when something on the computer doesn't work or make sense? Do you forget how to do things you know you should know, and do you ask a person at the railway station to issue you with a ticket rather than using the automatic ticketing machine?
When devices are confusing to use, or device functionality is hidden from view, it's likely that usability problems are getting in your way. Ideally, these problems should have been eliminated before the system was released, but we know that's often not the case. Many devices are difficult for people to learn and use because the Human-Computer Interaction issues were not addressed.
HCI is an inter-disciplinary discipline comprising experts from many fields, like engineering, computer science, psychology, graphic design, ergonomics and others. HCI is concerned with the design, evaluation and implementation of interactive technology. It aims to ensure that technology matches people's needs, capabilities and limitations, regardless of whether people work in groups or alone.
For more detail, the ACM SIGCHI Curriculum Development Group have a comprehensive document explaining
