scroll 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.e., viewed even if it does not fit into the space in a computer display, window, or viewport.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 to move the body of the document as well as two arrows on either end for precise adjustments. 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 .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, or "track" represents viewing the entire document, at which point the scrollbar may temporarily become hidden.
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