What is a spider web made of?
Protein. A spider web is a device created by a spider out of proteinaceous spider silk extruded from its spinnerets, generally meant to catch its prey. Spider webs have existed for at least 100 million years, as witnessed in a rare find of Early Cretaceous amber from Sussex, southern England. Many spiders build webs specifically to catch insects to eat. However, not all spiders catch their prey in webs, and some do not build webs at all.