What is the primary difference between ADP and ADRP?

The primary distinction between ADP (Army Doctrine Publication) and ADRP (Army Doctrine Reference Publication) stems from their respective roles in military doctrine. ADP serves as the overarching doctrine that outlines the principles and concepts of military operations, providing a foundational understanding of the subject matter. It articulates the "what" of military operations, defining core ideas and the framework for action.

On the other hand, ADRP is designed to expand on the ADP's concepts by detailing the "how to" aspects of implementing those ideas in practical scenarios. It provides guidance on the processes and procedures that support the principles introduced in the ADP, thus making the information more actionable for military personnel.

This distinction highlights why the answer accurately identifies the relationship between the two publications. By clarifying that ADP establishes the foundational doctrine and ADRP focuses on practical application, it emphasizes the complementary nature of both documents in the context of military training and operations.