HCI (human-computer interaction) is the study of how people interact with computers and to what extent computers are or are not developed for successful interaction with human beings.
As its name implies, HCI
consists of three parts: the user, the computer itself, and the ways they work
The goals of HCI are to produce usable and safe systems, as well as functional systems. In order o produce computer systems with good usability, developers must attempt to:
Underlying the whole theme of HCI is the belief that people using a computer system should come first. Their needs, capabilities and preferences for conducting various tasks should direct developers in the way that they design systems. People should not have to change the way that they use a system in order to fit in with it. Instead, the system should be designed to match their requirements.
Usability is one of the key concepts in HCI. It is concerned with making systems easy to learn and use. A usable system is:
Many everyday systems and
products seem to be designed with little regard to usability. This leads to
frustration, wasted time and errors. This list contains examples of interactive
mobile phone, computer, personal organizer, remote control, soft drink machine, coffee machine, ATM, ticket machine, library information system, the web, photocopier, watch, printer, stereo, calculator, videogame etc¦.
How many are actually easy, effortless, and enjoyable to use?
For example, a photocopier might have buttons like these on its control panel.
Imagine that you just put your document into the photocopier and set the photocopier to make 15 copies, sorted and stapled. Then you push the big button with the "C" to start making your copies.
What do you think will happen?
(a) The photocopier makes the copies correctly.
(b) The photocopier settings are cleared and no copies are made.
If you selected (b) you are right! The "C" stands for clear, not copy. The copy button is actually the button on the left with the "line in a diamond" symbol. This symbol is widely used on photocopiers, but is of little help to someone who is unfamiliar with this.
There are a large number
of factors which should be considered in the analysis and design of a system
using HCI principles. Many of these factors interact with each other, making
the analysis even more complex. The main factors are listed in the table below:
Training, job design, politics, roles, workorganisation
Noise, heating, lighting, ventilation
Health and Safety Factors
Cognitive processes and capabilities
Motivation, enjoyment, satisfaction, personality, experience
Seating, equipment, layout.
Input devices, output devices, dialogue structures, use of colour, icons, commands, navigation, graphics, natural language, user support, multimedia,
Easy, complex, novel, task allocation, monitoring, skills
Cost, timescales, budgets, staff, equipment, buildings
Hardware, software, application
Increase output, increase quality, decrease costs, decrease errors, increase innovation
The field of HCI covers
a wide range of topics, and its development has relied on contributions
from many disciplines. Some of the main disciplines which have contributed to HCI are:
o software design, development & maintenance
o User Interface Management Systems (UIMS) & User Interface Development Environments (UIDE)
o prototyping tools
o information processing
o cooperative working
o performance prediction
o social & organizational structures
o hardware design
o display readability
o natural language interfaces
o intelligent software
o Computer supported cooperative work (CSCW)
o graphic design
o engineering principles
(with thanks to Matt Jones)