Shell Variables and Linux
With the shell you can define your variables. When you define the variable, it is convention to use capital letters. When you want to use the variables, you add a '$' in front of the variable name. You can use variables within double quotes, but, not within single quotes. In addition, you some characters cannot be used within double quotes since they take on a different meaning. Fore example, '!' cannot be used within double quotes.
Declaring the Variable
root# VAR="Hello World"
Printing the Variable
root# echo $VAR Hello World root# echo "$VAR" Hello World