It’s generally a good idea to have your program produce some output; otherwise, someone may think it didn’t do anything. The
print() operator makes this possible. It takes a scalar argument and puts it out without any embellishment onto standard output. Unless you’ve done something odd, this will be your terminal display:
print "hello world\n"; # say hello world, followed by a newline print "The answer is "; print 6 * 7; print ".\n";
You can give
print "The answer is ", 6 * 7, ".\n";
This is a list, but we haven’t talked about lists yet, so we’ll put that off for later.
When a string literal is double-quoted, it is subject to variable interpolation  besides being checked for backslash escapes. This means that any scalar variable name in the string is replaced with its current value:
$meal = "brontosaurus steak"; $barney = "fred ate a $meal"; # $barney is now "fred ate a brontosaurus steak" $barney = 'fred ate a ' . $meal; # another way to write that
As you see on the last line above, you can get the same results without the double quotes. But the double-quoted string is often the more convenient way to write it.
If the scalar variable has never been given a value, the empty string is used instead:
$barney = "fred ate a $meat"; # $barney is now "fred ate a "
Don’t bother with interpolating if you have the one lone variable:
print "$fred"; # unneeded quote marks ...