A double headed arrow will display when the mouse cursor is pointed over a window or an object that can be resized. This is usually the edge or corner of a window. The arrow can be vertical or horizontal and is used to drag the object to increase or decrease its size.
Sizing Handle
two heanded arrow
Four-Headed Arrow.
There is only two things it changes to a arrow shaped pointer and a hand shaped pointer this is the default, pointer but others can be downloaded just be careful of virusses though.
arrow or triangle
A crosshair with 4 arrows.
The shape of the pointer when it is in a document is a triangle.
the pointer
the mouse pointer turn to arrow
4 way arrow
To resize a column, place the pointer on the right edge of the column heading until the pointer changes to a doubleheaded arrow. Click and drag to the right until the column expands to the width you want.
A mouse pointer