Dynamic DNS provides a persistent addressing method for devices (computers, routers, webcams) with dynamic external IP addresses.
This service is intended for assigning a good-looking and easy-to-remember permanent domain name to your networking device (such as a router), so that this name will not depend on what kind of IP address is used (dynamic or static). Hostname with dynamic DNS will be mapped to your dynamic IP address. When IP address is changed, dynamic DNS client will send a notification to the servers of the DNS-hosting service with a current IP address, and the changes will be propagated throughout the Internet in a matter of seconds.