In human terms: someone left the back door of their digital warehouse unlocked.
If you’ve ever stumbled upon a sparse, white page filled with blue links and folder icons while browsing the web, you’ve likely encountered a parent directory index of downloads
Simply dropping an empty index.html file into the folder will prevent the server from generating a file list. In human terms: someone left the back door
Index of /downloads/papers ; [PARENTDIR], Parent Directory, -. [ ], 2019-pm-info.pdf, 2019-04-01 08:13, 490K. [ ], 2019-pm-simple. tor-lattimore.com Index of /downloads - Goo Systems [ ], 2019-pm-info
"index of /downloads" + ".mp4" : Filters the directory search for specific file types.
It sounds like you may have stumbled upon a web page showing a (sometimes called an "index of /downloads" page). These pages appear when a web server has directory browsing enabled, allowing you to see all files and subfolders inside a given folder.