What is a cobweb?

Hey, Matt:

What's a cobweb? I say they're spider webs. My wife insists they're not, but she can't tell me where she thinks they come from. Settle the argument.

-- Mr. & Mrs. Clean, Santee

Mrs. Clean is in denial. She has spiders in her house. And also enough other bugs to make it worth the spiders' time to build a web. Cobwebs are simply spider webs made by a family of spiders with no sense of design. (Should I add that the black widow is in this family?) Because the webs are small and messy, the spiders prefer to build them in ceiling corners and the corners of windows; outdoors they opt for woodpiles or along walls. I'll leave you with this thought, which spiderologists are fond of repeating: Wherever you are, there's at least one spider within three feet of you.