5.1. File System Abstractions

The view of files, directories and file systems that is presented to users and applications is nearly entirely an abstraction. We begin by looking at the characteristics of drives and hard drives as the primary example. From there, we will describe how the abstractions are formed.

Secondary Storage

Storage that is permanent. Files may be stored on secondary storage devices.

5.1.1. Physical Hard Drives


5.1.2. Zone Bit Recording


5.1.3. Disk Partitions


5.1.4. Disk Block View

Logical Block Addressing (LBA)

Modern hardware uses LBA where the secondary storage device presents to the operating system numbered blocks of data. The firmware on the device handles the details of where (e.g. track and cylinder numbers) the data is stores.

5.2. A File


A file is an ordered collection of data blocks

5.3. Directories and File System Tables