The rights to use the domain names for a certain period of time, such as a year are registered through sites such as Network Solutions, Active Domain and so on. You can also register your domain name with the hosting company. The owners of the domains must renew the domains each time the subscription ends or they will no longer be able to use that name. If you want to know who is the current holder of the domain and the expiration date, you can check Who Is and enter the domain name. You can find more information here: http://whois.domaintools.com/
