It is the worlds most famous and open source CMS for fast web development, we can easily and efficiently build a huge site using Drupal. It provides excellent support for eCommerce  and  social networking sites.

One of the powerful features of the Drupal architecture are the specially named functions that allow your module to interact with the Drupal core.
These special functions are referred to as “hooks” because they let your module hook into the rest of the Drupal core.
The naming convention for these hooks is {modulename}_{hook},
where {modulename} is the name of your module and {hook} is a predefined string.
For example, if you had a module named “foo” and you wanted to place links into Drupal’s menu system, you would create a function called “foo_menu”.

You can set user permissions (add, edit, view) content or any block according to specified Role. It has very systematic approach to view information by using views or different contributed modules. It has great community support to solve you development related problem. So lets enjoy and use it.
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