Drush is a command-line tool that manages Drupal websites. It can create new Drupal sites, update and install plugins, update Drupal core to new versions, clear internal caches, backup and restore Drupal sites, and much more. Using Drush, it's possible to perform most site maintenance tasks from a shell rather than a web browser. More technical users may also extend Drush to add their own custom commands. Web developers may be interested in Drush's generate feature, which produces all the boilerplate files necessary to start creating a new theme or module. Drush needs to be run on a web server under PHP. It runs everywhere Drupal does, typically on a LAMP server. Drush is free software, licensed under the GNU General Public License, with source code available on GitHub. Most Linux distributions include a Drush package. Installation instructions for those that do not can be found in the Install section of the Drush website.