BDMV files are . You should only possess them if you:

stands for Blu-ray Disc Movie / Video . It’s a folder structure found on Blu-ray discs containing:

The keyword "young sheldon s04e18 bdmv" refers to the high-definition Blu-ray Disc Movie (BDMV) format of the Season 4 finale, titled "The Wild and Woolly World of Nonlinear Dynamics." This episode, which originally aired on May 13, 2021, is a pivotal chapter in the series that transitions the Cooper family toward the more serious emotional themes explored in later seasons.