Adobe Reader is a free program for viewing and printing PDF documents.
It includes an Adobe Acrobat browser plugin for displaying PDF documents within Firefox and other Web browsers. (By default, Firefox uses its built-in PDF Viewer.) This article provides resources for setting up Adobe Reader and the browser plugin on your computer.
To install Adobe Reader, please visit the Adobe.com website. To make sure your installation of Adobe Reader includes the latest available security and stability updates, open Adobe Reader, click on the Help menu and then click Check for Updates….
Viewing PDF files in Firefox
Click the following link to test how PDF files are displayed in Firefox: