Dynamic DNS is a feature that allows automatic update of your DNS's A or AAAA records, if your IP address is changed. If you have a server at home and host a website on your computer and you don’t have a static IP, the IP changes each time you reconnect to the Internet. To avoid manual update of your records everytime your IP changes, you can set up Dynamic DNS for your domain.
On every A and AAAA record you will see an icon with two arrows. When you click on them you will see the DynamicURL for this record. Every time you open this URL the record will be changed to the IP address of the computer the URL is opened from. On this window you will see options to open this URL with wget, php and perl scripts automatically.