design system – What is the meaning of Drive, Drive Compact, Focus, Focus Compact in Style Guide

When I read this article, https://design.lyft.com/building-a-design-system-library-3a1f0d09088f#2cf8 found following image.

Its talking about Frame Name

The frame name is the top-level grouping of the component, usually the
size (ie. Buttons have 4 sizes: Focus, Focus Compact, Drive, and Drive
Compact).

naming structure of button component

Middle of the image, there is a list called

  • Drive,
  • Drive Compact,
  • Focus,
  • Focus Compact,

what are they?