scroll bar - Computer Definition
A vertical bar on the right side of a window or a horizontal bar at the bottom of a window that is used to move the window contents up and down or left and right. The bar contains a "thumb", which looks like an elevator in a shaft. When dragged with the mouse, the window contents move correspondingly. When the bar is clicked above or below the thumb, the contents are moved a page at a time. The arrows are clicked to move one line at a time. Becoming Somewhat Obsolete Since the advent of scroll mice, which use a wheel for vertical and horizontal scrolling, the scroll bar is being used less and less on desktop applications. In addition, tablet and smartphone content is scrolled by fingers, and a scroll bar was never a natural part of the interface. See scroll mouse.