Reader Xi -11.0.01- — Adobe

Adobe broke naming convention with "XI" (Roman numeral 11) to emphasize a new philosophy: The reader should not just display, but act upon the document.

: Adobe officially ended support for Reader XI in October 2017 . It no longer receives security patches or bug fixes, making it highly vulnerable to modern exploits.

You can open PDF files by dragging them into the application window or using the File > Open menu.