Glocks would be a better way to describe them:
G19 is compact, shortened in grip and barrel vs. the G17. G26 is the subcompact, shortened in grip and barrel vs. the G19. G43 is the micro, basically between the G26 and 26 in grip and barrel, but single stack, resulting in a very small concealable 9mm. Some micros have double stacks, like the P365, Hellcat, and Gx4, for example. They are thinner than the G26, just barely thicker than the G43.