Explain drupal flow
Mainly, there are 5 important layers in Drupal where information flows,
a. Data (Node, ETC)
b. Modules
c. Blocks and Menus
d. User Permissions
e. Template
a. Data
The base of the system is group of Nodes. – the data pool
b. Modules
These are called functional plugins that are either part of the Drupal core or they ship with Drupal or they are contributed items which have been created by members of the Drupal community.
c. Blocks and Menus
Blocks and Menus is the next layer that we find blocks and menus. Blocks often offer the output from a module or can be created to display whatever you want, and then may be placed in various spots in your template (theme) layout. Blocks may be configured to output in various ways, as well as only showing on certain defined pages, or only for certain defined users.
d. User Permissions
Here is the next layer that settings are configured to determine what different kinds of users are allow to work & see.
e. Template
This is generally the site theme or the skin. This is made up predominantly of XHTML and CSS, with some PHP variables intermixed
Understanding this flow of information is very much important if you are facing A Drupal project targeted interview as the interviewer might test your overall knowledge of Drupal CMS by asking such sort of questions.