A conceptual understanding of file system, especially data structure and related terms will help you become a successful system administrator. I have seen many new Linux system administrator w/o any clue about file system. The conceptual knowledge can be applied to restore file system in an emergency situation.
What is a directory?
Directory is group of files. Directory is divided into two types:
Root directory - Strictly speaking, there is only one root directory in your system, which is denoted by / (forward slash). It is root of your entire file system and can not be renamed or deleted.
Sub directory - Directory under root (/) directory...
