From the Worldwide Developers Conference in San Francisco today, CNET editor Dan Ackerman posted the following picture:

Ackerman's unofficial title for his piece of photographic artwork? "WWDC explained in one photo." And, indeed. Though Tim Cook et al might beg to differ, the image certainly does explain at least one noteworthy aspect of such a developer's conference: specifically, its dearth of ladyfolk.

Which is why this particular type of photo -- evidence of one particular part of, er, technology's sausage being made -- has become a trope at tech-related confabs. The images document something funny and a little bit sad. They're evidence and wry commentary at the same time. They're the photographic version of the delightful Twitter account @WomenInLine, which exists to promote women in tech, it says, "so we can achieve the ultimate goal of having to wait in line at a software conference ladies' room."

Here's another entry in the genre, this one from the 2013 Consumer Electronics Show and shot by Kelly Clay:





And here's one from what looks to be the 2012 WWCD:





And here's one of the men's room alone shot at an unnamed "tech trade show" by Sarah Silbert:





And here's this year's Google I/O, this one from Engadget's Darren Murph: