glue v. paste

Historically, glue referred to liquid adhesives made from animal connective tissue. Glue is prepared by boiling animal parts that contain collagen (e.g., bones, hides, and hooves) to form gelatin, and adding water. In modern usage, any similar natural or synthetic liquid adhesive can be called glue.

Paste is a thick, soft, wet mixture of flour (or starch) and water used to affix paper or other light materials to surfaces.