Short for “Film doesn’t make you cool”. Used when somebody thinks that taking a photograph on light-sensitive film, instead of digitally, makes their photos better or more cool.
“Hey did you see the photos I took on my Canon AE-1?”
“Stop doing that bro, FDMUC.”
For Da ManDem ... Popular acronym used in the urban scene to use for anything you say that's aimed at fellow men. e.g. Xbox FDMD because men mainly play xbox.