Text 4. GUI

Graphical user interface (GUI) is a computer program that enables a person to communicate with a computer through the use of symbols, visual metaphors and pointing devices. Well-designed graphical user interfaces can free the user from learning complex command languages. On the other hand, many users find that they work more effectively with a command-driven interfaces, especially if they already know the command language. Best known for its implementation in Apple Inc.’s Macintosh and Microsoft Corporation’s Windows operating system, the GUI has replaced the arcane and difficult textual interfaces of earlier computing with a relatively intuitive system that has made computer operation not only easier to learn but more pleasant and natural.

Basic components of a GUI. Graphical user interfaces, such as Microsoft Windows and the one used by the Apple Macintosh, feature the following basic components:

· pointer: a symbol that appears on the display screen and that you move to select objects and commands, open files or starts software. The pointer also drags files to different folders. Usually, the pointer appears as a small angled arrow;

· pointing device: a device, such as a mouse or a trackball, that enables you to select objects on the display screen;

· icons: small pictures that represent commands, files, windows. By moving the pointer to the icon and pressing a mouse button you can execute a command or convert the icon into a window;

· desktop: the area on the display screen where icons are grouped is often referred to as the desktop because the icons are intended to represent real objects ion a real desktop;

· windows: you can divide the screen into different areas. In each window, you can run a different program or display a different file. You can move windows around the display screen and change their shape and size at will;

· menus: most graphical user interfaces let you execute commands by selecting a choice from a menu.

In addition to their visual components, GUI also makes it easier to move data from one application to another. A true GUI includes standard formats for representing text and graphics. Because the formats are well-defined, different programs that run under a common GUI can share data. This makes it possible, for example, to copy a graph created by a spreadsheet program into a document created by a word processor.