Balance force - There are two forces acting upon the book. One force - the Earth's gravitational pull - exerts a downward force.

Unbalaced forces - Whatever the case, our focus is not upon the history of the book but rather upon the current situation of a book sliding to the right across a tabletop. The book is in motion and at the moment there is no one pushing it to the right.
Balanced force- are two forces acting opposite directions or an object and equal in size, anytime there is balanced force on an object, the object stay still or continues moving at the same speed an in the same direction

Unbalanced force- in two individual forces are of equal magnitude and opposite direction, then the forces are said to be balanced. an object is said to be acted upon by an unbalanced force only when there is a an individual forces that is not being balanced by force of equal magnitude and in the opposite direction