With Views are built all the lists of content in the default Drupal 8 vanilla installation. The front page list, the admin content overview page, all the taxonomy term, user lists etc.
Knowing how to use Views means not only that you can add bells and whistles to those pages, to make them look as you wish but also that you can create complete new pages, blocks with content, featured articles lists and much more.
Theming in Drupal 8 is a bit different than it was for the previous versions, so there are plenty of things for the developers to catch up with or learn. We've tried to structure this course in a way that you will dive with each video a bit deeper than the previous one and that you will gradually learn all the basic concepts there are to know about Drupal 8 theming.