World wide developers have contributed over 8,000 modules which extend the functionality of Drupal. Drupal is open source and is contstantly being enhanced as Drupal 7 was released in Jan of 2011 and Drupal 8 is underway. Open Source means that the code to can be copied, shared, and modified. Anyone can download, use and change Drupal code and contribute changes back to the Drupal for other people to share and use. You don't have to pay liscensings fees, and thier is no proprietary "black box" code which only a few developers know.
Drupal has over 600,000 users on Drupal.org. This thriving community is complete with local meetups in almost every major US city (including Drupal WDC and Drupal NYC) and 2 DrupalCon Worldwide conferences yearly.
Drupal has been around for over 10 years.
Drupal is less expensive to develop than Plone because PHP developers are easier to find that Python developers and Drupal doesn't require special server requirements. Drupal has password security is compatible with the requirements for US government agencies. Drupal boasts 43 official members of the dedicated security team.
Each new Drupal website rides on the foundation and module code created by other talented programmers. Your website benefits and your company hasn't had to pay for much of the powerful infrastructure. Drupal allows for features such as Custom Contect Types, Revision Control, User Management just to name a few.
Drupal development is funded and supported by big industry players including Google, Sony Music and the Knight Foundation.
Drupal is integrated with Google Analytics and plays well with Search Engines and is Standards-compliant HTML/CSS. Every page has the ability to customize and optimize the URL, and modify meta tags, page titles etc.
Drupal has modular code which is easy to modify to fit your requirements. This means that you are future-proofing your business. Your business changes, your Drupal code is flexible enough to change with you without having to rebuild the site from scratch. Drupal also integrates well with 3rd Party applications including (XMLRPC, Soap, Rest, Json)
Drupal allows you to create multi lingual sites easily. Each page can be assigned different languages and those page will be added to the menu whcih server that language automatically. Each page uses flags to denote all of the languages where it is available.
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