Today, computerized mechanism and ICT (information and communication technology) have a significant impact on human life process. What was on the top of the Maslow's Hierarchy of Needs is now performing a vital role in each human life. Due to the swift growth in the technology industry and hardware and software development computerized systems and machines are used on an everyday basis by almost everyone, even people from different fields which are not related to computing. Major sectors such as aviation, healthcare, banking and education adopted computer technology to improve productivity and efficiency. Interaction between human and machine occurs in user interface and the communication mode between user and a computer system is influenced by the design of user interface (Dix et al, 2004). Poor design criteria in the user-interface will produce difficulty and waste of time when user try to interact with a computer. As Shniedermann (2000) claim “Designers of older technologies such as Postal Services, Telephones, and television have reached the goal of universal usability, but computing technology is too difficult to use for many people. One survey of 6000 computer users found an average of 5.1 hours per week wasted trying to use computer. More time is wasted in front of computers than on highways” (Shniedermann, 2000). When designing a user interface for a user centered system, designers and developers must concentrate on human factors and ergonomics to validate the usability, approachability and user safety of the system (Preece.J, 1994). And human factors must be taken into account at the beginning stages of the design. More often, it is taken into consideration at the end stages of the design, this will lead to costly changes or unwilling to change the design. A good interactive system must have the both usability and technology to produce an effective output (Collura, 2004).
3. Topic Overview 3.1 HCI
The word HCI (Human-Computer interaction) and the study of human factors became universally accessible and used by the system developers since the early 1980s. The study of human factors and ergonomics defines how physical attributes of computer or machine affect user performance (Dix et al, 2004, p3). The word Human computer interaction may give contradictory interpretations from different fields of view. HCI as a system design discipline, it is a set of disciplines or studies which are developed by research on human factors and computer factors (Fetagi et al, 2007). HCI is a study or discipline of human factors and how human interact with machines, which helps to improve the usability of the system. And it focuses on the psychological, physical and theoretical facets of an interaction (Dix et al, 2004). The Design principals of the HCI must be applied in interface design to ensure ease of use, safety, learnability, efficiency, accessibility and simplicity of the system (Stephanidis, 2001).
Human Computer Interaction disciplines
4. Research findings
Importance of applying HCI principles in interface design
“If you think about the complexity of most computer systems you can see that the potential for poorly designed HCI is very high” (Preece.J, 1994). Surveys demonstrate that 50% of programming and design of a human centered system is dedicated to user interface (Mayers, 92). A well designed user interface will increase efficiency of output at an individual level, for example, doctors can easily identify problems and pilots can fly with more accurately and safely (Shneiderman, 2001). “Applications developers who apply HCI principles in user interface design are producing exciting interactive systems” (Shneiderman, 2001). The main goals of applying HCI principles in interface design are usability and safety (Preece.J, 1994). The term usability describes how easy to learn the system and how casually users can use it once they have learnt it (Nielsen &...