The document outlines the use of storage policies and disk types in Hadoop HDFS, detailing how different types of storage can be utilized to optimize performance and cost-efficiency through intelligent tiering. It emphasizes the importance of data access frequency and age in effectively managing storage and highlights the automated tools that can be employed to move seldom accessed data to more cost-effective storage solutions. Additionally, it discusses the benefits of external solutions like factordata hdfsplus for simplifying the tiering process without requiring changes to the existing Hadoop cluster.