ATTENTION ALL GIRLS ALL GIRLS!!! Go to your photos and type in the ‘Brassiere’ why are apple saving these and made it a folder!!?!!?😱😱😱😱
— ell (@ellieeewbu) October 30, 2017
On Monday, several Twitter users noticed that on Apple products running iOS 10 or newer, the Photos app uses object recognition to automatically sort pictures featuring bras into a folder named "brassiere." Several women at The FADER tried searching for "brassiere" in their Photos app on Monday afternoon and were shown an album of pictures of their cleavage.
The update that made this possible was announced in June 2016. TechCrunch reported at the time, "The computer vision tech used by Apple runs natively on your iPhone or iPad, meaning that it doesn’t require you to upload all the images to the cloud. In can recognize faces in your photos and group by person, but it also has advanced object recognition, making it possible to find images of any number of different things from your distant past."
At launch time, Apple reportedly used 4,432 different keywords in all of its recognized languages to sort your photos. Judging by that original list, and subsequent searches by FADER staff, it doesn't appear to recognize any other risqué categories or any equivalent categories for men like "underwear" or "boxers." It does have folders for "shower," "bathtub," and "sunbathing," though.
It's worth mentioning that Google has been doing object recognition similar to this for photos since at least 2013. In 2016, Facebook made some of their own object recognition tools open source. A representative for Apple was not immediately available for comment.