It refers to a liquid that can reduce the intermolecular forces of certain solids or liquids, thereby dispersing the dissolved substances into a homogeneous system of molecules or ions. According to Coating Online, commonly used solvents are low-viscosity liquid substances, mainly including aliphatic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, esters, alcohols, ketones, acids, ethers, terpenes, amides, and water. However, most organic solvents have certain toxicity, flammability, and explosiveness; they cause environmental pollution, pose potential safety hazards, and are harmful to the human body.