"Domaining is the business of buying, selling, developing and monetizing Internet domain names. Such domain name portfolios often include marketable generic dictionary-word domain names, or domains whose registrations had lapsed yet still retain reasonable traffic. There is sometimes no actual intent to use any of the domain names with the exception of generating advertising revenue through domain parking. Domain names are the addresses of the web and come in a wide variety of extensions (.com being the most popular)."  (Source: Wikipedia.org)