DEFINING THE USER INTERFACE
• User interface, design is a subset of a field of study called human-computer interaction
• Human-computer interaction is the study, planning, and design of how people and
computers work together so that
a person's needs are satisfied in the most effective way.
• HCI designers must consider a variety of factors:
– what people want and expect, physical limitations and abilities people possess,
--how information processing systems work,
– what people find enjoyable and attractive.
– Technical characteristics and limitations of the computer hardware and software
must also be considered.
The user interface is to
– the part of a computer and its software that people can see, hear, touch, talk
to, or otherwise understand or direct.
The user interface has essentially two components: input and output.
Input is how a person communicates his / her needs to the computer.
– Some common input components are the keyboard, mouse, trackball,
one's finger, and one's voice.
Output is how the computer conveys the results of its computations and
requirements to the user.
– Today, the most common computer output mechanism is the display
screen, followed by mechanisms that take advantage of a person's auditory
capabilities: voice and sound.
The use of the human senses of smell and touch output in interface design still
remain largely unexplored.
• Proper interface design will provide a mix of well-designed input and output
mechanisms that satisfy the user's needs, capabilities, and limitations in the most
effective way possible.
• The best interface is one that it not noticed, one that permits the user to focus on the
information and task at hand, not the mechanisms used to present the information and
perform the task.