The Domain Name System (DNS) is a hierarchical decentralized naming system for computers, services, or other resources connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities. It translates more readily memorized domain names to the numerical IP addresses needed for locating and identifying computer services and devices with the underlying network protocols. By providing a worldwide, distributed directory service, the Domain Name System is an essential component of the functionality on the Internet, that has been in use since 1985.
How to Change DNS Server on macOS
Go to SystemPreferences >>> Network.
Select the Internet connection you’re connected to, and click Advanced.
Select the tab marked DNS.
Click the DNS servers in the box on the left and click the – button.
Now click the + button and add DNS servers of your choice.