The hydrophobic effect occurs when nonpolar substances aggregate in aqueous solutions and exclude water. The word hydrophobic means water-fearing minimizes the contact between water and nonpolar substances. For example, the hydrophobic effect is responsible for the separation of oil and water/ Hydrophobicity also plays a significant role in cellular membranes, formation of vesicles, protein folding, small molecule-protein interactions. Materials with an affinity for water, where water spreads across in order to maximizing contact are known as hydrophilic. Hydrophobic surfaces are where water self-segregates or the surface repels water, causing droplets to form. Hydrophobicity is the association of non-polar groups or molecules in an aqueous environment which arises from the tendency of water to exclude non-polar molecules.