1. Oxygen's electron configuration: Oxygen has six electrons in its outer shell, and it needs two more to complete its octet. It achieves this by forming two covalent bonds with two hydrogen atoms.

2. Lone pairs of electrons: Oxygen has two lone pairs of electrons in its outer shell. These lone pairs repel the bonding pairs of electrons, pushing the two hydrogen atoms closer together.

3. VSEPR theory: The Valence Shell Electron Pair Repulsion (VSEPR) theory states that electron pairs around a central atom will arrange themselves to minimize repulsion. The two lone pairs on oxygen exert a stronger repulsive force than the bonding pairs, causing the hydrogen atoms to be pushed down, resulting in a bent shape.

4. Hybridization: Oxygen's atomic orbitals hybridize to form four sp3 hybrid orbitals. Two of these orbitals form covalent bonds with the hydrogen atoms, while the other two orbitals are occupied by the lone pairs. This hybridization further contributes to the bent shape.

In summary: The bent shape of water is a result of the combination of oxygen's electron configuration, lone pair repulsion, and VSEPR theory. This bent shape gives water many unique properties, such as its high polarity and ability to form hydrogen bonds.