In Linux and Unix-like operating systems, the
echo command is used to print text or the value of a variable to the terminal. When used in combination with a shell variable, the
$ symbol is used to reference the value of that variable.
For example, if you have a variable named
foo that has been set to the value
bar, running the command
echo $foo will print
bar to the terminal. This is because the
$foo notation is used to reference the value stored in the
echo $ is run, it will print the value of the current shell environment variable, which is empty, it will print nothing. The shell environment variable is a special kind of variable that is used to store information about the current shell session, such as the current working directory, the user’s home directory, and other system-related information.
echo command also have different options and flags you can use with it. such as
-n option to not print the new line at the end of the string and
-e option to enable the interpretation of backslash escapes, like newline and tab.
echo -n "This is a test" #This will not print a newline at the end echo -e "This is a test\nThis is a new line" #This will interpret the newline escape sequence and print the string on two lines
echo $ is a command used in Linux and Unix-like operating systems to print the value of the current shell environment variable to the terminal. It will print nothing as the value is empty.