The document summarizes molecular structure and covalent bonding theories. It discusses valence shell electron pair repulsion (VSEPR) theory and valence bond (VB) theory. It describes the linear, trigonal planar, tetrahedral, trigonal bipyramidal, and octahedral electron pair geometries that result based on the number of electron pairs around a central atom. It also discusses how the presence of lone pairs can result in different electronic and molecular geometries, and the relationship between molecular geometry and polarity. Examples of various molecular shapes are provided.