Real-URL is a Chrome add-on that allows users to redirect to a different URL when accessing a non-existent URL. The destination URL is calculated based on a password registered in the browser, without accessing the page's content, only using the URL pattern.

The concept behind Real-URL is to provide a way to hide certain files or pages on the web. While it is common to restrict access to secret files by implementing access restrictions, there may be situations where it is better to make the files invisible to others while still being visible to the owner. For example, if a user wants to work on an unfinished draft page, instead of it showing as "Not Found" when accessed normally, Real-URL can redirect to a draft page where the user can make edits without others seeing it.

Real-URL is a convenient tool for keeping certain files or pages hidden within a public folder. It eliminates the need for server-side access restrictions, making it a simple and easy solution.