General theory of relativity

I heard that a junior to me, once asked our physics teacher,"Ok, I understand that there is gravity,but could you tell me why everything is pulled towards the centre because of this gravity?" Our teacher branded his question idiotic and the class laughed at him and called him a psycho.They even started calling him Einstein!( I wish somebody call me by this name too, let it alone be in the derogatory sense).
With due respect to my teacher, I have pity for her because she had no idea about this grand "General Theory Of Relativity". Had it not been Einstein, everyone would have thought that gravity is but a force like all the other forces. But Einstein revolutionised Physics with the concept"Gravity is not a force but a consequence of presence of mass on the fabric of universe". To understand this let us visualise a stretched rubber or elastic. Now let us suppose that a heavy object is placed at the centre of this. Due to it's mass, the heavy object will bend or warp the surface of the rubber.Similar is the case with gravity. the presence of earth, sun, moon.., with their mass warp or bend the fabric of the universe. There is slope or bending of the space time towards the masses.More the mass, more is the bending and hence more is the gravity. Mass bends or warps the space time around it and this consequence of warping of space time which slides any object near the bending, to fall into the centre of the mass is called Gravity.