This chapter explores the general format of your Red Hat Enterprise Linux file system. It bridges the differences between using Nautilus to manage the files on your system and using a shell prompt to manage them. It does not go into the minute details of using a shell prompt; those will be covered in Chapter 4 Shell Prompt Basics. This chapter orients you to the system as a whole, and then you can choose which method of management you prefer.
Due to system security, unless you are root, you are not allowed to gain access to all system-level files and directories. If you do not have the permission to open, delete, or execute a file, an error message is displayed showing your access has been denied. This is normal behavior and is used to prevent non-privileged users from modifying or deleting important system files.
Below are a few terms to know before we begin our discussion of the file system.
An extension is that part of a filename that is found after the final ".". In the filename foo.txt ".txt" is the file's extension. Extensions are used to indicate file type.
A path is the string of directories and sub-directories you would have to navigate through in order to reach a given location in the file system.
To have root access means to be logged in using the root account. This can be done from the main login screen, a shell prompt, or any application that requires your root password. Root access means that the user has permission to do anything on the system, so use root access with care.
The root directory is the top-most directory of the file system. All other files and directories exist in this directory or one of its sub-directories. Do not confuse the root directory, /, with root's home directory, /root/.