Yes, we are talking about file routes or resource routes here. Just like HTML routes, the files which generate these sit in the `src/pages` folder of your Astro project. Common examples are serving a PDF file or JSON data, though you are by no means limited to those. The sky is the limit! For the PDF file on a static Astro site, you just generate the file content in a JavaScript file named, for example, `src/pages/datasheet.pdf.js`. This will be accessible from the `https://example.com/datasheet.pdf` href on the final site. In that file, you will want to return an object with a `body` field. The value of that field will be a string set to the PDF file content. For an SSR site, name the file `src/pages/datasheet.js`. Now you will return an HTTP Response object. You can add a content-type header of `application/pdf`.