The Latin - English expression icon (from the Greek εἰκών to icon or icon for " little picture ") is used in computer science to designate a small image or pictogram that, as part of a graphical user interface, often contains a file or directory and, similarly, one on each button Indicates command to the applications. For applications localized in the German language , it is usually referred to as a symbol .
Features and ergonomics
Icons are mostly square and have standard sizes with edge lengths of 16, 24, 32, 48, 64, 128 or 256 but also 512 pixels . Due to the limited memory of computers, only a limited number of colors were used in the past, e.g. For example, in earlier versions of Microsoft Windows 16 or 256 colors. Today, most work environments no longer have any limits (in some cases 16.7 million colors are standard). Many different image formats are used, the most common being ICO and PNG . In the meantime, freely scalable vector graphics are also used, e.g. B. SVG .
Software without icons is hard to imagine today. Nevertheless, the following applies: The user must first learn the meaning of each icon. Therefore, its meaning should be as easy to recognize as possible for the user. The creator of an icon is therefore well advised to test his designs with people in the target group. For this purpose, the frequency of assignment between an icon and a term or the uniqueness of the associations to an icon is usually considered. However, more recent studies suggest that the speed with which an icon is selected and emotional aspects (“The icon is appealing”) should also be included in the evaluation. One advantage of icons is their high recognition value.
Icons are an important component in file managers for graphical user interfaces ( English short GUIs ). Depending on the setting, the action assigned to the icon is carried out with a single mouse click or with a double click (e.g. starting a program, opening an image file with an image processing program or playing a sound file). The icons are mostly related to the file types or the associated program, i. That is, text files have the symbol of a text block or help files have a question mark.
Following the example of the Apple Macintosh , most operating systems and user interfaces equate a double-click on an icon with the command "Open". A (double) click on a program icon starts the associated program. The program or file name is usually under or next to the icon . If you point the mouse pointer over an icon without clicking, a more detailed information block is often visible.
Icons in toolbars usually have the function of a button . They are used to symbolize program functions or associated commands such as printing , saving , bold type , etc. These are usually triggered with a simple click of the mouse.
Depending on the desktop environment used, it is possible to place important icons on the desktop or in the toolbars of programs so that certain programs can be started quickly or files can be opened quickly.
Icons can be created and edited with special icon editors . These offer numerous templates and editing tools and can handle various file formats.
- Rayan Abdullah, Roger Hübner: Pictograms and Icons. Compulsory or optional? Verlag Hermann Schmidt, Mainz, 2005, ISBN 3-87439-649-5 .
- Alexander Christian: Pictograms. Critical contribution to a definition. Shaker, Aachen, 2009, ISBN 978-3-8322-8021-5 .
- Jochen Gros: Icon typing, pictograms and icons in OpenType . BoD, 2006, ISBN 3-8334-3261-6 .