What is Human-Computer Interaction?
Human-computer interaction (HCI) is the field that studies how people communicate and work with computers. Its goal is to design systems that are easy, comfortable and efficient for people to use. The meeting point between the user and the computer is called the user interface.
Key idea
The user interface is the part of a system that people see and use to give commands and receive feedback from the computer.
Types of User Interface
There are several types of user interface:
- Command-line interface (CLI) — the user types text commands. Powerful but harder to learn.
- Graphical user interface (GUI) — uses clickable icons, windows, buttons and menus. Easy to learn.
- Menu-driven interface — the user chooses from a list of options, suitable for machines such as ATMs.
- Natural user interface (NUI) — uses touch, voice or gestures, as on a smartphone.
Example
When you tap the touch screen of a phone to open an app, you are using a graphical user interface that is also natural (touch). In contrast, a system administrator who types dir to list files is using a command-line interface.
Why Usability Matters
Usability is a measure of how easy and pleasant a system is to use. An interface with high usability lets users complete tasks quickly, make few mistakes and feel comfortable. Poor usability makes users confused, wastes time and may cause them to stop using the system.
Remember
HCI = the study of human–computer interaction. User interface = the meeting point. GUI is easy, CLI is powerful. High usability = easy, fast, few mistakes.