HCI

HCI, or human–computer interaction, is an interdisciplinary field that studies the design, evaluation, and implementation of interactive computing systems for human use. It examines the interfaces between people and technology across devices, software, and networks, with the goal of making systems usable, efficient, and engaging.

The field draws on ergonomics, cognitive psychology, and computer science. It gained prominence with graphical user interfaces in the 1980s and has evolved to cover a wide range of modalities and settings. Influential thinkers such as Ben Shneiderman and Jakob Nielsen promoted usability principles and evaluation methods, building on earlier work by pioneers like Douglas Engelbart.

Core concepts include usability (effectiveness, efficiency, and satisfaction), user-centered design, and accessibility. Designers consider affordances, feedback, mental models, and cognitive load to create inclusive experiences. HCI emphasizes user needs and contexts, iterative design, and empirical validation through observation and testing.

Common methods are prototyping, usability testing, heuristic evaluation, task analysis, and think-aloud protocols. Evaluation uses metrics such as task success, time on task, error rate, and standardized scales like the System Usability Scale. These methods guide iterative improvements and collaboration among developers, designers, and users.

Applications span consumer electronics, enterprise software, healthcare, education, and automotive interfaces. Emerging areas include voice and conversational interfaces, touch and gesture, virtual and augmented reality, and assistive technologies. Accessibility standards, such as WCAG, influence design and compliance, while ethical considerations increasingly shape research and practice.

Current trends emphasize multimodal interaction, AI-assisted design, privacy, and inclusive, equitable technology.