Only the IP address changes regularly, when you have an Dynamic IP. To know whether your Internet service provider provides Static (or) Dynamic IP address, visit the site
http://www.ip-details.com . Just reset (or) unplug the modem you are using. Again switch on the modem back and check the same site. If your IP address differs from the previous one, it is Dynamic IP. No changes happens (or) remains the same IP address, its nothing but Static IP. You can make a request to change your static IP through Internet service provider.