These buttons are found in the top right-hand corner of a window, and allow you to control that window in certain ways. To use each of these buttons, click on them with the left mouse button. To resize a window, click on this corner with the left mouse button, then keeping the mouse button held down, move the mouse to a new position, and the window will be resized. The diagram on the right shows a vertical scroll bar and the effect of clicking on, or dragging the various parts with the left mouse button. The size of the central slider normally gives an indication of the proportion of the document that is currently visible.
Some scroll bars have extra buttons at the bottom with double arrows.
These are used for moving up or down a page at a time. Dialogue boxes Dialogue boxes are special windows used by programs to prompt the user for extra information. If you want to save or print your document, you will need to learn how to use dialogue boxes. An example of a dialogue box is shown below. Not all dialogue boxes will look like this one, but most of the components of them are similar.