Final answer:
The operating system level provides the standardized interface that enables applications to interact with file systems and devices without dealing with hardware specifics.
Step-by-step explanation:
An Operating System (OS) is a collection of software that manages computer hardware resources and provides common services for computer programs. The operating system is the most important type of system software in a computer system. The operating system level provides a standard interface between applications and the file systems and devices that hold the data. This level is essential as it abstracts the complexities of hardware management, ensuring that applications can perform operations like reading, writing, and deleting files without needing to understand the specifics of the underlying hardware and file system architecture.
For instance, when you open a document using a word processor, the operating system handles the intricacies of locating the document on the storage device, loading it into memory, and permitting the word processor to manipulate the content without directly interacting with the disk hardware.