Examples of horizontal and vertical scroll bars around a text box

A scrollbar is a graphical widget in a GUI with which continuous text, pictures or anything else can be scrolled including time in video applications, i. In computer programming a widget (or control) is an element of a Graphical user interface (GUI that displays an information arrangement changeable by the user In Computer graphics, Movies, Television, and other kinetic displays scrolling is sliding text images or video across a monitor or display e. , viewed even if it does not fit into the space in a computer display, window, or viewport. A visual display unit, often called simply a monitor or display, is a piece of Electrical equipment which displays images generated from the Video In Computing, a window is a visual area usually rectangular in shape containing some kind of User interface, displaying the output of and allowing input for one

Usually designed as a long rectangular area on one or two sides of the viewing area, containing a bar (or thumb) that can be dragged along a trough (or track) to move the body of the document as well as two arrows on either end for precise adjustments. In Computing, a mouse gesture is a way of combining Computer mouse movements and Clicks which the Software recognizes as a specific The "thumb" has different names in different environments: on the Macintosh it is called a "thumb" on the Java platform it is called "thumb" or "knob"; Microsoft's . Mac OS X version 104 “Tiger” was the fifth major release of Mac OS X, Apple’s desktop and server Operating system for Macintosh NET documentation refers to it as "scroll box" or "scroll thumb"; in other environments it is called "elevator", "quint", "puck" or "wiper". Additional functions may be found, such as zooming in/out or various application-specific tools. The thumb can also sometimes be adjusted by dragging its ends. In this case it would adjust both the position and the zooming of the document, where the size of the thumb represents the degree of zooming applied. A thumb that completely fills the trough indicates that the entire document is being viewed, at which point the scrollbar may temporarily become hidden.

Scrollbars can be seen as a computer representation of a thumb, with which you thumb through pages of documents. The thumb is the medial -most digit of the hand The English adjective for thumb is pollical

A scrollbar should be distinguished from a slider which is another widget that works in a similar fashion, the difference being that the slider is used to change values, and does not change the display or move the area that is shown. A slider is a graphical widget in a GUI with which a user may set a value by moving an indicator usually in a horizontal fashion

Manipulation

While dragging the thumb is historically the traditional way of manipulating the widget, a scroll wheel may also be used. In Computing, a mouse (plural mice, mouse devices, or mouses) In addition, the arrow buttons may be clicked to scroll a small amount, or the trough above or below the thumb for a larger amount. Sometimes, both arrow buttons appear next to each other for quick, precise manipulation without having to drag the thumb or move the mouse great distances to the other arrow; one of them may also be duplicated so as to show at both ends of the bar, providing familiarity for those used to both separate and adjacent buttons.

Another system for manipulating them is to look at which mouse button was pressed. For instance, a left-click might cause it to scroll down, while a right click would scroll up, and the middle button could be used to place the thumb precisely. This form requires less fine motor skills, although it requires a multi-button mouse, and possibly a greater degree of GUI literacy. A motor skill is generally agreed as a learned skill that involves voluntary movement to complete a task

Simultaneous 2D-scrolling

Special scroll-bar like widgets allow panning around a two dimensional space by simply moving a single rectangle in any direction on the plane. For example the GtkScrollpane is implemented in the text viewers gv and ghostview. Ghostscript is a suite of Software based on an interpreter for Adobe Systems ' PostScript and Portable Document Format (PDF Page description Another example for simultaneous two-dimensional scrolling is an alignment program for protein sequences. Initially, the horizontal scroll-bar looks like a conventional one. But then the scroll-bar offers three additional features:

1. It provides an overview of the entire scene.
2. The height can be enlarged.
3. The knob can not only be moved left and right but also up and down for vertical scrolling.

Customization

The ability and specific methods needed to customize the look and function of scrollbars can vary significantly based on which operating system or software application you are attempting to customize. An operating system (commonly abbreviated OS and O/S) is the software component of a Computer system that is responsible for the management and coordination Application software is a subclass of Computer software that employs the capabilities of a computer directly and thoroughly to a task that the user wishes to perform The most commonly used method of altering the look-and-feel of the scrollbar in Web pages is to use a set of non-standardized CSS directives which at the time of this writing were only supported by Microsoft Internet Explorer versions 5. A web page or webpage is a resource of information that is suitable for the World Wide Web and can be accessed through a Web browser. Windows Internet Explorer (formerly Microsoft Internet Explorer abbreviated MSIE) commonly abbreviated to IE, is a series of graphical x or higher.

See also

• Scroll Lock
• Slider

External links

• An Interactive IE Scrollbar Customization Tool
• IE Scroll Bar CSS Style Generator
• Animated scrollbar component for flash