Download File Synchronisation Software Simon Grimshaw Computer Science

There are two main types of user interface to be considered in creating this software, they are a
command based interface, like MS-DOS, or a graphical user interface, like Windows, both the
advantages and disadvantages will be discussed below. There are other types of interfaces available to
use, like speech recognition, but with the requirements of the project, i.e. can be used over multiple
devices, it is best to concentrate on the two main types of interface which are available on most
systems.
2.5.1 Theories
There are many different theories about different HCI techniques; each theory adds something new to
the field, either in graphical interface design to how colours should be used in an interface. Some of
the theories are worth considering, but not all the theories are considered ‘correct’ and there is some
debate about certain theories. That’s why it is more important to look at the theories but pay more
attention to the guidelines that are available; the reason for this is that the guidelines are generally
more agreed upon.
2.5.2 Command Based User Interface
Command based user interfaces have in numbers in recent years due to the release of such operating
systems like Microsoft Windows, which are designed to run GUI. Even though the market has more
GUI interface it is still worth considering a command based interface. A command based user
interface has both advantages and disadvantages and it is important to look at these in deciding which
type of interface to make.
When designing the user interface there are a number of different options to be considered in how the
commands can be entered. The first is just a single command, e.g. ‘run’ the command which will
carry out just a single task. If only a small system is in use then this approach maybe suitable as there
is only a handful of command needs to be remember and is simple to learn. However for larger
systems such as UNIX and some text based editors where the number of commands is large these type
of commands become difficult to remember and not as easy for the user to learn. The next step up
from using just a single command word is to use a command word and an argument, e.g. ‘print stuff’.
This type technique can help larger systems as the number of commands needed to remember can be
reduced and it can speed up the execution of the programs. However it does have some disadvantages,
the system becomes harder to create because checks have to be made to make sure every argument is
compatible with the argument. Another option is a command, option, and then an argument, for
example ‘print 3 stuff’. Like the command-argument option this choice creates more option for the
final user and can speed up the execution of larger systems, however for smaller systems this choice
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