When a window opens on a computer screen, it is surrounded by borders. This is called window border. This border allows you to resize the window. The window can only be lengthened, or just widened, or widened or reduced at once. Because each window is rectangular, each window has two borders along the length and two borders along the width. To move the window to the side, that is, to the right or to the left, move the mouse pointer over the width (vertical) border, and drag or drop the window by dragging and dropping the left mouse button. In the same way, to move the window up or down, move the mouse pointer over the (horizontal) border along the length and raise or lower it by dragging. If the user wants to increase or decrease the length and width of the window at the same time, the mouse pointer must be moved to any one of the four angular points of the corresponding window.
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