* Gravity is weak: Gravity is the weakest of the four fundamental forces in nature. It's much weaker than electromagnetic forces, which are responsible for holding atoms together, or the strong and weak nuclear forces, which govern the nucleus of an atom.
* Mass matters: The force of gravity depends on the masses of the objects involved. While the Earth has a massive gravitational pull, a book has a very small mass compared to the Earth.
* Distance matters: The force of gravity weakens rapidly as the distance between objects increases. The book is close to you, but still quite far away compared to the Earth's center of gravity.
Imagine this: You're standing on a giant trampoline. A bowling ball (Earth) is placed in the center, causing a big dip. You (a small person) and a feather (the book) are on the trampoline. The bowling ball pulls you and the feather towards it, but the feather is so light, the pull is barely noticeable. You, however, will feel the pull of the bowling ball more strongly.
So, while we don't feel it directly, the force of gravity between you and a book is still there. It's just too small to notice!
