The "mp4" version of these 19th-century sequences is a digital reconstruction. Modern archivists take the original still frames from Muybridge’s plates and sequence them at a standard frame rate (usually 12–24 fps) to create a smooth video file. Clarifying "The First Film"

The title appears to be a modern misnomer or a clickbait title for a specific sequence from Eadweard Muybridge’s pioneering photographic studies. While no film of that exact name exists in the historical record, it likely refers to one of Muybridge's chronophotographic experiments from his 1878-1887 series, Animal Locomotion . Historical Context of 1878 "Films"

: His work included famous sequences like "Sallie Gardner at a Gallop" (1878) and various human movements such as "Woman Kicking" (1887) or "Annabelle’s Serpentine Dance" (1895, by the Lumière brothers). Why the MP4 Exists Today

: These still frames were later projected using a Zoopraxiscope , a rotating glass disc that created a brief, looping illusion of motion—similar to a modern-day GIF.