Using the Resize Borders
The four borders of a view window are called resize borders because dragging them resizes the view window. For example, by dragging the right or left resize border, you can change the width of the view window. Similarly, by dragging the top or bottom resize border you can change the height of the view window. By dragging a corner of the resize border, you can change both the height and width of a view window. The pointer indicates the directions in which you can drag the border or corner.