So what is configuration in Drupal terms?

In Drupal, configuration includes topics such as content types, fields, menus, or text formats. Creating or changing a configuration on a live site poses a high risk and makes changes untraceable. Questions such as who made a change, and when and why it was made, cannot be answered.

Up until Drupal 7, Drupal had all configuration stored in the database. By Drupal 7, most professional Drupal developers kept track of their configuration changes by exporting them to code, the most popular option being the Features module, and version-controlling it with a version control system such as Git.