The document explains the Drush tool, a command line interface for managing Drupal installations, and specifically focuses on Drush Make, which automates the process of setting up a complete Drupal site by parsing a configuration file. It emphasizes the efficiency and ease of using Drush Make to include various components such as Drupal core, modules, themes, and external libraries. The document also provides examples and guidance on creating makefiles, highlighting the time-saving benefits of using Drush Make for consistent installations.