2007 PhD Thesis Final Revised.pdf - Curtin University

Unfortunately, the development of such technologies was hampered by the
otherwise successful introduction of the GUI. Historically, the introduction of the
GUI to the general public heralded many significant advantages to personal
computing. These included the ability to comprehend symbols faster than text, the
fostering of more concrete thinking, the establishment of context, more attractive
presentation and the ability to reverse incorrect actions easily (Galitz, 2002). As the
advantages of the first GUI offerings were recognised, other computer
manufacturers scrambled to produce their own versions of GUI-based operating
systems. For the IBM-PC platform, the IBM OS/2 and Microsoft Windows in the
late 1980s and early 1990s encouraged further software development in support of
these GUI interfaces (Lessard, 2004). Currently there are three major variants of
operating systems in the home market. Two of these operating system families,
Microsoft Windows and UNIX-based variants such as Linux, run on computer
hardware based on the original x86 PC architecture pioneered by the IBM-PC. The
other OS is Mac OS which is supported by a combination of generic and Apple-
propriety hardware. In terms of usage, the different variants of Microsoft Windows
combined represent approximately 90% of the x86-based PC market share with
UNIX-based operating systems, such as Linux, representing nearly all of the
remaining 10% of users. Computers based on the original x86 PC architecture
represent 97% of worldwide computer sales. The Macintosh has an estimated 2-3%
of the worldwide market, yet it is highly regarded in key industry areas and retains a
loyal user base (Davison, 2004). The specific features of these operating systems
are discussed in section 6.5.1.
Although the advantages of the GUI and its current market dominance enable
the GUI to be highly productive, the greatest advantage in using a graphical interface
over a command-line interface is the fact that most people find visual learning easier
and more natural. It has been noted that “…in human beings, actions and visual
skills emerged before languages” (Galitz, 2002, p19). While the move away from
text towards graphics ensured that computing would become inherently easier for the
general mainstream population, for people who are blind or vision impaired the
fundamental advance of visual learning in computing effectively destroyed the
ability for this group to use a computer for many years. The GUI not only created
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