The graphical user interface (GUI) is a special type of software in common
use today. It can be part of the operating system software, or it can be a complete
application program on its own; at times, a GUI (pronounced “gooey”)
seems to straddle the line between operating and application software. The
basic design of any GUI is that it stands between the operator of the computer
and the computer itself and acts as the go-between. Any GUI has
two primary goals: (1) to shield the operator from needing a great amount
of technical knowledge to use the computer effectively and correctly; and
(2) to give a consistent “look-and-feel” to application programs (if they are
designed for it).
Accomplishing the first goal means that an operator can perform all necessary
technical tasks (e.g., copying data files between disks, backing up
information) by pointing at icons (small pictures) on the screen. These icons
represent the tasks that can be done. For example, by pointing to an icon that
represents a desired data file and then dragging that icon over onto another
icon that represents a printer, a person can print the file. Note that because of
the GUI’s capabilities, the person did not have to know the correct operating
system commands to print the file.
Accomplishing the second goal means that any application program can be
designed so it is less difficult for a person to learn how to use it. Basically, the
GUI defines a standard set of functions that it can provide (e.g., open a data
file, save a data file, print a data file) and gives standard ways for application
programs to use these functions. If application programs are designed and
built to use these functions, a person has to learn only once how to open a
data file. Any other program that uses theGUIfunctions has the same “lookand-
feel”; that is, a person can open a data file in the same manner. Doing
things in a consistent, predictable way not only reduces a person’s learning
time but increases a person’s comfort level and productivity. Figure 2.4 is an
example of a main menu for a nursing software package.