Why is it that a book on a table does not move?

The forces that can be in between the book and table. While considering the forces between the book and the table, also keep in mind the state of motion (state of rest or state of motion) of the book.

Frictional force is the force that exists between an object and a surface when the object is only in contact with or sliding over the surface. The frictional force is determined by the surface's smoothness and roughness. 

The downward force of gravity and the upward force of the table on the book are equal in size and opposing in direction. These two forces counteract each other. However, no force is available to balance the force of friction.

Hence, A book on a table does not move because forces of the table pushing up and gravity pulling down are balanced.