Cobweb spiders, belonging to the family Theridiidae, are known for their irregular, tangled webs. These webs are often found in corners of buildings, under furniture, and in other sheltered areas. Cobweb spiders are typically small and can vary in color, but many have a distinctive rounded abdomen. These spiders are beneficial as they help control pest populations by preying on insects that get caught in their webs. While some cobweb spiders can bite, they are generally harmless to humans. Common examples include the common house spider and the black widow spider, which are both part of this diverse family.