What Are Libraries? for Drupal 8, Drupal 9

Last updated February 5, 2020

In Drupal 8, CSS and JavaScript are loaded bundled together as asset libraries, and then these libraries are loaded via either themes or modules. Asset libraries can contain one or more CSS assets, one or more JS assets and one or more JS settings. In this tutorial we'll cover what asset libraries are, what they contain, and the problem that they are trying to solve.