If you change it the .jl file in a editor you could quite easily make it unreadable to pluto. > That would contradict the claim in the article that Pluto file

If you change it the .jl file in a editor you could quite easily make it unreadable to pluto. > That would contradict the claim in the article that Pluto files are just regular julia files. Not really, no. The files pluto generates are a subset of valid julia files. All Pluto files are valid julia files; not all valid julia files are valid Pluto files.