Why do we call lenses that let in more light "fast?" "Stops" are a doubling or halving of light and don't actually stop anything? International Organization of Standardization = ISO...not IOS? WHY!!?? 

Yeah, a lot of the terminology used in photography and cinematography is just bonkers and doesn't make a whole lot of rational sense—which is kind of the case with a lot of professional terminologies—and if you're confused, amused, or angered by these strange, sometimes misleading terms, you should check out this video by photographers Tony and Chelsea Northrup and laugh—or rage—or flood the comments with your nerdery and accurate explanations. 

"Depth of Field...what kind of fancy ass person made this term?"

To my fellow nerds, I get it. These terms make a lot more sense when you look at the linguistical and technical origins of their baptismal names. But to my fellow priests of reason, I friggin' get it! These terms confused the absolute hell out of me when I first started. I literally couldn't grasp how a lens with an f1.4 aperture let in more light than one with an f2.8. Bigger numbers should equal bigger aperture, right!? Am I crazy!? 

"But V, it's a dimensionless number that is a quantitative measure of lens speed." Yeah thanks, Wikipedia. That means nothing to me. And "bokeh!?" What in the hell does that m—oh—it literally means "blur" in Japanese. Perfection.

Source: Tony & Chelsea Northrup