Surfactants are ingredients that enable the cleaner to lift away stains, oil or grease. You can think of surfactant molecules as having two sides—a tail and a head. The tail is hydrophobic, or water-hating. It surrounds the stain that you are trying to remove from your clothes. The head is hydrophilic, or water-loving. It sticks close to the water molecules and lifts the stain away.