$foo             # Scalar
$foo[$i]         # Array element, a scalar
$foo{$k}         # Hash element, a scalar

@foo             # Array contents, a list of scalar values
@foo[$i, $j]     # Array slice, a list of scalar values
@foo{$k1, $k2}   # Hash slice, a list of scalar values

%foo             # Hash contents, a list of key-value pairs