What is the concept of gravity and how does it affect us on Earth (as compared to the Solar System)?

Gravity is a
natural force of attraction between two physical objects.  The gravitational force between two
objects is directly proportional to the masses of the objects and inversely proportional to the
distance between them.  In other words, the more massive the objects, the stronger the gravity. 
Also, the further the two objects move apart, the smaller the gravitational effect becomes. 
So...