on how computer systems should be designed for
people to allow them to interact with computer
systems successfully (Waddell and all, 2016a). A
human-computer system is made up of the two core
components: the user interface core and the functional
core. The user interface is the part of the computer
system which users use to interact with the computer
system, and which accepts or captures user inputs
(Kraleva, 2017). The user inputs are then processed
to produce outputs or results for users via the user
interface, using a functional core part of the computer
system (Waddell and all, 2016b).
In the earliest years of computer systems, few
people had access to computers because the only form
of computer interaction was through the submission
of commands to the computer system (Sinha, 2010).
Computer systems were used by professionals like
academics, scientists and computer programmers, or
anyone who had knowledge about how to write
computer commands (Myers, 2002). Computers have
become part of our lives because the world we live in
is flooded with computers, from home to the
workplace (Waddell and all, 2016c). Computers have
changed the way we do things, and they have
advanced as time went. The way computers used to
look and operate in the 1970s is different from how
computers look and operate nowadays. Since people
started using computers in the 1970s, they have raised
questions about computer interfaces and how they
interact with computer systems.
In simple terms, computer interactivity occurs
when a computer responds to user inputs or actions
(Bostan, 2015a). Waddell, Zhang, and Sunda
described human-computer interaction as a
“multidisciplinary topic concerned with the
evaluation, design, and implementation of interactive
computing systems for human use and with the study
of major phenomena surrounding them” (Waddell
and all, 2016c).
An example of computer interactivity is when a
person plays computer games or video games; this
form of interactivity requires a gamer to continue
interacting with the game. Another example is when
a person interacts with the web browser to fill in a
form so as to register for an email account, with the
browser providing output to the user. What makes a
computer unique is the fact that computers are
interactive. Consider the example of a person playing
a computer game, where the person is consumed by
the game in a way that the player sees himself or
herself inside the game because the communication
between the player and the game is highly responsive.
In gaming, watching someone else playing a
computer game is not as interesting as when you are
playing the game, the reason for this being that there
is a lack of interactivity in this scenario, and this
shows how important it is for computer systems to be
interactive (Bostan, 2015b).
2.3 Computing Usability Challenges
and Principles
Many systems and application designers develop
systems without having users in mind, and, not
getting any feedback from users on what they want,
they only focus on what is documented on their
requirements document. One thing that all system
designers have in mind is that users don’t have any
technical knowledge of how systems are designed and
developed. Users know exactly what they want, as
much they don`t have any solid technical knowledge
on how systems are developed. The problem with
designing systems is that users are different, and they
all have different design requirements, which makes
it difficult for designers to design interfaces that will
accommodate all users at once. Since users have
different requirements, it is impossible for designers
to develop interfaces that are usable for the first time.
After the first interface design, designers are likely to
continue updating the interface based on user
requirements.
The usability problem is defined as a set of factors
that block users from meeting their goals or
completing their tasks when using a system or an
application, where this is caused by poor user
interface design factors and factors of the usage
context (Manakhov and Ivanov, 2016). The number
of computer and internet users has grown
exponentially, and this includes novice, average, and
super-experienced users. Given the growing number
of computer and internet users, applications should be
easy to use and learn to use, but users face problems
every time when interacting with most applications
(Alarcon and al, 2014). Alarcon, Medina, and
Villarroel conducted quantitative research to ensure
the quality of web applications. The research
analysed the usability and communicability problems
of the transactional web application of an online store
called “Ripley” to determine the application’s quality,
since the website is used by people who live in Chile.
Alarcon, Medina, and Villarroel used a heuristic
evaluation testing method to test the usability of the
application. The researchers found 18 usability
problems. Alarcon, Medina, and Villarroel's research
showed how they successfully used different methods
to find the usability and communicability problems of
the application, and this was significant because the
research showed how each problem was identified