There are lots of content management systems out there. Most of which are open source and normally get the job done. However, Drupal stands out amongst them for a host of reasons, five of which are
All the open source CMS out there have user communities that help out each other. However, the Drupal community out there is second to none. It is helpful to users of all levels from the complete noob to the most advanced. Once you have a question and ask it right and politely, you are sure to get an answer.
You can call them extensions, addons or any other name.
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