Hot melt adhesives are thermoplastic materials that are solid at room temperature but melt when heated. They are commonly used in various industries for bonding materials like paper, wood, and plastics. When applied, they cool and solidify quickly, creating a strong bond. These adhesives are popular due to their ease of use and versatility. They can be applied using a hot glue gun or other heating equipment, making them suitable for both industrial and DIY projects. Additionally, they are known for their fast setting time and resistance to moisture, enhancing their effectiveness in many applications.