$$array[0]      # Short for ${ $array }[0]
${ $array }[0]  # The first element of the array referenced by $array
${ $array[0] }  # The scalar referenced by the first element of @array

##</code><code>##

"foo$varbar"     # Equivalent to "foo" . $varbar
"foo${var}bar"   # Equivalent to "foo" . $var . "bar"