A friend asked me the other day, "What are cobwebs and why in the world are they called that?"

I told him that I thought I knew that the "cobweb" dangling in the corner was made from spiders - the cobweb was left behind like a safety line as the spider moved about. It never was a web. These leftover strands are sticky and as a result dirt and dust stick to them, causing a buildup and creating what we call "cobwebs." I went on to explain that only some species are "cobweb" spiders."Common house spiders" are the culprits. What? House spiders? Not outside spiders? No, house spiders. Living in my house?Yes. The good news is that they are predators feeding on household pests such as flies, mosquitoes, ants and wasps. There are a number of these house spiders and they are actually called "cobweb weavers."Achaearanea tepidariorum is the scientific name for the common house spider found here in Pennsylvania and rather impressive, if you ask me. This spider is extremely common in our homes and its webs can be found in corners and around the windows of our homes.Females are 5-6 millimeters (about ¼ inch) in length and larger than the males who are about 2-4 millimeters (about ⅛ inch) in length. Coloring can range from yellow to brown with "chevron" markings along the back. The female's legs are yellow with brown bands. The males' legs are orange with brown bands. Males and females will live for longer than a year, staying around the web and mating often. And they will live their entire lives inside.They do not venture outside for any reason. Egg sacs are almost teardrop-shaped and may contain as many as 300-350 eggs. It is possible for a female to produce up to 17 of these sacs during a lifetime, resulting in more than 4,000 eggs.Within a week, spiderlings hatch from their protective egg sac. After hatching, air currents disperse surviving spiderlings on threads of silk. This is known as "ballooning" or "kiting." Perhaps you remember the movie "Charlotte's Web" and recall mama spider bidding her spiderlings goodbye as they floated off in the breeze.The good news is that these spiders are nonaggressive and rarely (if ever) bite people. And, the better news is that if one were to bite due to being trapped in a shoe or in a sleeve of a coat, for most people the reaction to the bite is minimal. Most people are not even aware they were bitten until they notice a red, itchy bump. The redness and itchiness disappear in about an hour and there is no cause for concern. American house spiders possess poor vision and cannot detect any movement more than 3-4 inches away. If cornered, they will feign death as last resort rather than bite.Not all spider webs are cobwebs but all cobwebs are the "work" of a spider. So, why the word "cobweb"? I searched a few favorite word sites and found one that claims the word coppe was Middle English or Dutch for spider. So, therefore coppeweb meant the web of a coupe (spider).Oh! It all makes perfect sense now.Of course in 1275, they probably didn't know or care that the coppeweb wasn't really a web at all.