What do you think the "F" in "F-hole" stands for? Something dirty? Get your mind out of the gutter. It the first letter of "Fissure". Sometimes, when they make guitars, the top splits. If they have too much labor into the thing, many manufacturers try to sell it anyway. Some folks even like it! Of course, there's no accounting for taste, so we can let that go even though it encourages substandard product offerings. But, it's actually a major flaw, and unacceptable to people who don't need to store dust, spiders, dandruff, spilled beer, cobs and their unsightly webs, hair, etc. Not to mention hooker dust. Who invented that stuff, anyway?