A software distribution or (distro) is a collection of software components built, assembled, and configured so that it can essentially be used "as is".
Varbase is a Drupal distribution. It packages several adaptive functionalities and essential modules into its powerhouse. It takes advantage of Drupal core modules, as well as other famous and contributed modules and software components.
Since Varbase is a Drupal distribution, any Drupal compatible module, theme, library, can be used and utilized with Varbase.