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A n I n t ro d u c t i o n t o H u m a n I n t e r f a c e s
The role of human interfaces
Human-computer interfaces are at the crossroads of a number of fields of computing
science such as ergonomics, computer graphics, operating systems, human factors, and
cognitive psychology. In the early days of computers the basic input devices were paper
tape, punch cards and the keyboard, but now the most common interfaces are the key-
board, mouse and gaming-console controller.
A key factor in the recent development of human-computer interaction technologies
is the concept of user-centred design, a concept based on four primary design principles:
- A clear understanding of user requirements and tasks being solved;
- Incorporating user feedback to refine requirements;
- Involvement of user in formative evaluation of the design; and
- Integrating user-centred design with other development tasks and activities.
While the significance of these principles to the design and development of Human-
Computer Interaction (HCI) devices appears obvious to us now, this has not always
been the case. Some predicted improvements in HCI include better quality of inter-
action, easier use and increased speed. The last of these seeks to allow users to spend less
time on human-interaction tasks and more on new experiences. This is often facilitated
by involving more of the user's senses or via total immersion in the computer environ-
It is interesting to note that while new devices often emerge specifically to answer the
needs of a set application area, developments in these areas usually provide powerful
feedback for ideas about human-computer interaction in general. Computer graphics
have fulfilled such a role in the past. Now, multimodality, ubiquitous computing, co-
operative work, and virtual environments, including cyberspace and augmented reality,
are rapidly developing and arousing interest in creation and use of new devices that will
continue to change the range of concepts of human-computer interaction.
Multimodality: the stimulation of multiple senses
The past decades have been marked by a fundamental reliance on the visual output
from computer systems.Visual devices such as monitors have been and remain the most
popular output devices, used in combination with the keyboard and mouse as means of
data input.The introduction and recent developments of graphical user interfaces (GUI's)
mark a clear tendency towards overload of the visual channels. As the ability of technolo-
gy to handle images, audio, and video improves increasing attention is being paid to the
development of support a wider array of multi-sensory data including odours, texture,
and space.This does not mean that visual technologies are being left behind. In fact, they
are continuing to be developed in order to achieve greater reality and portability.
Ubiquitous computing
Ubiquitous computing is often defined as the flipside of virtual reality. Mark
Weiser, the inventor of the concept explains, `Where virtual reality puts people inside a
computer-generated world, ubiquitous computing forces the computer to live out here
in the world with people.Virtual reality is primarily a horse power problem; ubiquitous
Human Interfaces