What's the difference between the logical and physical structure of a file? What are the advantages of not having an application program interact directly with the physical file structure?

In the computer storage memory, a logical file structure refers to a collection of files which are set-up in an organized way inside different directories, folders/sub-folders and storage volumes. While a physical file structure of a file refers to the physical storage place which are arranged linearly as an address space.

PART B:

It is important not to have application programs interacting directly with the physical file structure because they (Application programs) already have a logical view of the computer's secondary storage, so application programs can have faster maneuvering and access to stored data