The IRLE notes that blue collar and manual workers can be replaced for an average cost of $2,000, while the average cost for managerial and professional employees may be as high as $7,000.
By defining a Node * typedef, it is assured that all the variables will be structure pointer types, or say, that each variable is a pointer type pointing to a structure type.
The string class is an instantiation of the basic_string class template that uses char (i.e., bytes) as its character type, with its default char_traits and allocator types (see basic_string for more info on the template).