Drupal Overview:

• Nodes:  Content is created based on "node" type (such as story, blog, book)
• Themes:  Content presentation is determined based on the chosen "theme"
• Blocks:  Content is displayed on each site page based on the configuration of "blocks"
• Modules:  Content creation, use and administration is facilitated by "modules".
• Taxonomy:  Content is organized based on a category structure refered to in Drupal as "taxonomy"
• Menus: Site navigation is facilitated by use of site "menus"

Resources: 

• Introduction to Drupal Terminology
• Basic Site Configuration