Types of directories
Directories can be defined by the operating system, by the system administrator, or by users.
The system-defined directories contain specific kinds of system files, such as commands. At the top of the file system hierarchy is the system-defined /(root) directory. The /(root) directory usually contains the following standard system-related directories:
| Item | Description |
|---|---|
| /dev | Contains special files for I/O devices. |
| /etc | Contains files for system initialization and system management. |
| /home | Contains login directories for the system users. |
| /tmp | Contains files that are temporary and are automatically deleted after a specified number of days. |
| /usr | Contains the lpp, include, and other system directories. |
| /usr/bin | Contains user-executable programs. |
Some directories, such as your login or home directory ($HOME), are defined and customized by the system administrator. When you log in to the operating system, the login directory is the current directory.
Directories that you create are called user-defined directories. These directories allow you to organize and maintain your files.