# Basic syntax:
printenv

#Just use following structure to store output of command into a variable:
var=$(command)
#For example:
var=$(echo 'hi')	#store hi into var
var=$(ls)	#store list of files into var

#!/bin/bash
echo
echo "When single quote is used with string:"
invitation='Welcome to javatpoint'
echo $invitation
echo
echo "When double quote is used with string:"
invitation="Welcome to javatpoint"
echo $invitation
echo
echo "When variable is used with double quote:"
Remark="Hello User!, $invitation"
echo $Remark
echo
echo "When variable is used with single quote:"
Remark='Hello User!, $invitation'
echo $Remark
echo 

# Example:
MY_VAR=a # here you assigned the value 'a' to MY_VAR
echo $MY_VAR
echo MY_VAR
# output:
a
MY_VAR
# good practice says to name variable in all caps to differ from commands
# if you want to print to print to console the value of MY_VAR, you must use $
# if you echo without using $, the name of the variable will be printed
# not the value