Small-scale ARG (Alternate Reality Game) creators or "creepypasta" enthusiasts sometimes use clinical-sounding filenames to give their videos a "found footage" or mysterious feel, though no major "Mary" mystery is currently trending under this exact name. How to Open the File
In a professional or security setting, this often serves as a label for a specific camera (e.g., "Mary" vs. "Paul"), a project name, or a user who uploaded the clip. 264-Mary.mp4
Many CCTV and IP camera systems (like Frigate ) use H.264 compression and auto-generate filenames based on camera names and timestamps. "Mary" vs. "Paul")