Many species of spiders are common household pests in the United States.  Certain common household spiders spin webs over lamps, in corners and in basements.  This createsw an unsightly situation but causes no real harm.  Rememter that every "cobweb" was made by a spider.  Although  all spiders use venom when they bite and kill their prey, the black widow and the brown recluse spders are the only North American species consistently dangerous to humans.