Van der Waals forces are weak attractions that occur between molecules or parts of molecules. They arise from temporary shifts in electron density, which create small, localized charges. These forces play a crucial role in various physical properties, such as boiling and melting points, and are significant in the behavior of gases and liquids. There are three main types of Van der Waals forces: London dispersion forces, dipole-dipole interactions, and dipole-induced dipole interactions. Although individually weak, they collectively contribute to the stability and structure of larger molecular systems, influencing everything from the formation of biological membranes to the properties of polymers.