What is Drupal?
What is CMS?
What is a web content Management system?
Which are commonly used PHP based CMSs?
What is an Open source software?
What are GNU Licenses? / Does free software mean using the GPL?
Why are so many Drupal versions available – 4.x, 5.x …? Which one should I use?
Can I use Drupal on the command line?
What are hooks in Drupal?
What is Database abstraction layer in Drupal?