Drupal

• Drupal is a free content management framework for Windows and Linux operating systems. This application is customizable with hundreds of modules created by a developer community. The software has five main sections of appearance with customizable themes, management of content and a user management section called People. You can download themes from the Drupal website or find themes on the Internet. These themes can be altered for user-specific needs. Management of content is done with creating menus and adding nodes such as blog posts or other types of article modules. There are various add-on modules that allow you to export files to formats such as PDFs. Drupal also has adaptable structure and configuration settings.
  
  

Joomla

• Joomla is a free and open-source content management system and application framework available for Windows, Linux and Mac operating systems. Joomla offers a Contact Manager to help you organize and find contact information. The application has a robust security system where there are four levels of user access for configuration and content access. Joomla offers both document and media file management with a WYSIWYG editor, templates, and downloaded extensions from a developer community. You can export Joomla content to files such as CSV and PDF.
  
  

Plone

• Plone is free software for Windows, Mac and Linux operating systems. The software offers point-and-click installation for Windows and Mac. The Linux distribution comes in a unified installer or as a DEB package that you can install in Ubuntu Linux if dependencies like "zope-cmfplone (= 2.1.2-2)" are established. The software offers such content management features as indexing of Word and PDF documents, wiki support and inline editing. You can scale images and have automatic generation of image galleries in thumbnail format. This content can be exported to formats like CSV and PDF. Plone is a strong package that has high security configurations for both desktop and Web applications. The FBI and the CIA both rely on Plone applications for content management security. However, the software is flexible, with extensions and templates created by a developer community.
  
  

Typo3

• Typo3 is free software that works on Linux, Microsoft Windows, OS/2, FreeBSD and Mac OS X. The software also has support for browsers such as Internet Explorer, Firefox, Netscape, Opera and Konqueror on Windows, UNIX or Mac. Typo3 is managed through WYSIWYG editors, customizable templates and developer-created extensions such as multimedia management. You can work with copy and paste functions and export to multiple document formats. There's a built-in spell-checker and a directory-tree format to make finding files or pages easy. Typo3 administrators have security features like user management, auditing and a sandbox to try new features securely.