Bilbo wakes from his restful dreams of bacon and eggs when he felt something touch him. He quickly becomes aware of a strong sticky substance being wrapped around his lower body and realized that one of the giant spiders of Mirkwood was wrapping him in a spider web.
This moment in the novel exemplifies Bilbo's change from passive traveler to potential hero. He quickly cuts his bonds, kills the spider, chases the remaining spiders away, and helps to free the dwarves. Bilbo's experience with the spiders builds his self-confidence, and he begins to see himself as a valuable member of the company instead of a burden.