Why is a water molecule non-linear?

Valence Shell Electron Pair Repulsion Theory (VSEPR) states that lone pairs repel other lone pairs more so than they do bonded pairs. In water, the oxygen atom has two lone pairs. These two lone pairs repel the hydrogen-oxygen bonded pairs so much that the molecule is at its lowest energy arrangement when the H-O-H bond angle is 104.5 degrees. As a result, the water molecule can be classified as non-linear.