London dispersion forces are weak intermolecular attractions that occur between all atoms and molecules. They arise from temporary fluctuations in electron distribution, which create instantaneous dipoles. These dipoles can induce similar dipoles in neighboring particles, leading to a brief attraction. These forces are particularly significant in nonpolar molecules, where other types of intermolecular forces, like hydrogen bonding or dipole-dipole interactions, are absent. Although individually weak, the cumulative effect of many London dispersion forces can significantly influence the physical properties of substances, such as boiling and melting points.