A user interface, as recently described, is a collection of techniques and mechanisms to interact with something. In a graphical interface, the primary interaction mechanism is a pointing device of some kind. This device is the electronic equivalent to the human hand. What the user interacts with is a collection of elements referred to as objects. They can be seen, heard, touched, or otherwise perceived. Objects are always visible to the user and are used to perform tasks. They are interacted with as entities independent of all other objects. People perform operations, called actions, on objects. The operations include accessing and modifying objects by pointing, selecting, and manipulating. All objects have standard resulting behaviors.
The Popularity of Graphics
Graphics revolutionized design and the user interface. A graphical screen bore scant resemblance to its earlier text-based colleagues. Whereas the older text-based screen possessed a one-dimensional, text-oriented, form-like quality, graphic screens assumed a three-dimensional look. Information floated in windows, small rectangular boxes that seemed to rise above the background plane. Windows could also float above other windows. Controls appeared to rise above the screen and move when activated. Lines appeared to be etched into the screen. Information could appear and disappear as needed, and in some cases text could be replaced by graphical images called icons. These icons could represent objects or actions.
Screen navigation and commands are executed through menu bars and pull-down menus. Menus “pop up” on the screen. In the screen body, selection fields such as radio buttons, check boxes, list boxes, and palettes co-existed with the reliable old text entry field. More sophisticated text entry fields with attached or drop-down menus of alternative options also became available. Screen objects and actions are typically selected through use of pointing mechanisms, such as the mouse or joystick, instead of the traditional keyboard.
Increased computer power and the vast improvement in the display enable a system to react to the user’s actions quickly, dynamically, and meaningfully. This new interface was characterized as representing one’s “desktop” with scattered notes, papers, and objects such as files, trays, and trash cans arrayed around the screen. It is sometimes referred to as the WIMP interface: windows, icons, menus, and pointing device.
Graphic presentation of information utilizes a person’s information-processing capabilities much more effectively than other presentation methods. Properly used, it reduces the requirement for perceptual and mental information recoding and re-organization, and also reduces the memory loads. It permits faster information transfer between computers and people by permitting more visual comparisons of amounts, trends, or relationships; more compact representation of information; and simplificationof the perception of structure. Graphics also can add appeal or charm to the interface and permit greater customization to create a unique corporate or organization style.