The full form of DDNS is Dynamic Domain Name Service. It’s used on Computing ,Networking in Worldwide

Dynamic DNS Services are used by small companies and individuals when they want to publish a service on the Internet, and that service is hosted within an internal or home network.

Home networks typically uses a NAT router to connect to the internet which means that devices located on the internal network aren’t accessible from the Internet.

In the following discussion we are going to assume that we want to make a web server located on an internal server available on the internet.

Dynamic DNS keeps DNS records automatically up to date when an IP address changes.

Dynamic DNS is used in large networks that host internal services, and use their own internal DNS and DHCP servers.

However small companies, and home networks don’t normally have their own DNS server so why would they need Dynamic DNS ?

DNS stands for Domain Name System, It’s like the white page directory for the Internet. You supply a name, DNS supplies a number. The name in this case is specifically a hostname and the number is an IP address. Without DNS you would have to remember every IP address of every website you want to visit.