Drush Make is a command line tool used to build a Drupal codebase from a set of instructions. It is part of the Drush suite of tools, which are used to manage and maintain Drupal websites. Drush Make is used to create a Drupal codebase from a single text file, known as a makefile. The makefile contains instructions for downloading and assembling the necessary components of a Drupal codebase, such as modules, themes, and libraries. Drush Make can also be used to update an existing codebase, by downloading and installing the latest versions of the components specified in the makefile. Drush Make is a powerful tool for managing and maintaining a Drupal codebase, and is an essential part of the Drupal developer's toolkit.