The term glue applies to protein derivatives made from animal or vegetable protein. White and yellow woodworking glues are made by the traditional method of boiling down bones.

Glues are usually sold in the form of granules or flakes which are heated and dissolved in water before being used. They are applied hot and harden both by cooling and the absorption or evaporation of water. Animal and fish glues are also made in a liquid form that is used cold.

The principal uses of glue are in woodworking and the manufacture of coated abrasives such as sandpaper. All of the animal and vegetable glues may be attacked by fungus under conditions of high temperature and humidity.