This is the root. (./index.html)
The other files in this deploy are:
./foo.html
./bar/index.html
NOTE: This is the default site configuration when creating a Netlify Site.
/foo.html - Resolves to file contents - Anchor target in DOM still /foo.html (not re-written)
/foo - Resolves to file contents
/foo/ - 301 to /foo
/bar.html - 301 to /bar/ - Anchor target in DOM still /bar.html (not re-written)
/bar - 301 to /bar/
/bar/ - Resolves to file contents
This follows historical web parlance of document vs. directory-index for trailing slashes
This is also good for SEO (content not duplicated across trailing slash and non-trailing-slash variants)