class InspecPlugins::ResourcePack::Plugin

This simple class handles the plugin definition, so calling it simply Plugin is OK.

Inspec.plugin returns various Classes, intended to be superclasses for various

plugin components. Here, the one-arg form gives you the Plugin Definition superclass, which mainly gives you access to the hook / plugin_type DSL.

The number '2' says you are asking for version 2 of the plugin API. If there are

future versions, InSpec promises plugin API v2 will work for at least two more InSpec major versions.