Spiders are easily identified by their eight legs and round bodies. When they stay outdoors, spiders can be beneficial as a form of pest control as they tend to eat harmful insects. However, the sight of a spider inside of a home can cause many people to react with fear. In the home, spiders can quickly spread, leaving their webs throughout the house. Even the most common household spider can cause painful bites, while poisonous spiders can warrant a trip to the emergency room. When spiders begin to invade a home, it is time to take action in order to keep the members of the household safe.