From the description:

Bullet hell shmups, rail shooters, run ‘n’ gun… THESE NAMES ARE INCONSISTENT AND CONFUSING. In the first episode of the Belmont Index, let’s look through history to definitively categorize the industry’s first genre.

Chapters:
00:00 - Introduction
06:31 - PART 1: Fixed, Area, & Tube
14:51 - PART 2: Top-Down, Platforming, Gallery, & Rail
27:50 - PART 3: Shmups
37:00 - What’s Next?