EXAMPLE

Variable Name	Description
PATH	A colon-separated list of directories in which the shell looks for executable files. When a user types a command into the shell, it searches for the corresponding executable in each directory listed in the PATH variable until it finds a match.
HOME	The current user's home directory. This is the default directory that the shell opens in when a user logs in. It's also used as the base directory for a number of other configuration files and user-specific data.
USER	The username of the current user. This is used to identify the user when logging in and is also used by some programs to determine file ownership and access permissions.
LANG	The system's default language setting. This variable specifies the language used for system messages and error messages, as well as the default character set used for text input and output.
PWD	The current working directory. This variable stores the full path to the directory that the user is currently working in. This can be useful for scripting and automation tasks.
SHELL	The path to the current user's default shell. This variable stores the path to the shell that is currently running. This can be useful for shell scripts that need to know which shell is being used.