At some point, you may need to view and/or edit the configuration settings for your site.
The settings.php file contains website-specific configuration information, including the Drupal database settings. To view the file in your Drupal codebase, go to (your_docroot)/sites/default/settings.php.
The following list provides examples of settings that you can configure:
The type, username, password, host, and database name settings for your database. In addition, you can set target fall-back databases and the encoding format in which Drupal stores its data, for example UTF-8.
The location and name of one or more directories containing a settings.php file determine which one is addressed when loading your Drupal website(s). This enables you to install multiple Drupal websites or define subsites that run on a single Drupal codebase.
update.php
By default, the settings.php file blocks access to the update script, update.php, for non-site-administrators. You should not leave it accessible to other users.
This is an optional setting that establishes the base URL of your website (http://site_URL) to help resolve conflicts between different website domains.
You can set and alter various PHP settings for your website, such as session lifetime and session cookie lifetime.