This article explains how to change the DNS server settings on a router, computer, or other devices.

When you change the DNS servers that your router, computer, or other Internet-connected device uses, you change the servers (usually assigned by your Internet service provider) that the computer or device uses to resolve host names to IP addresses.

In other words, you change the service provider that resolves www.facebook.com to 173.252.110.27.

Changing DNS servers can be a good step if you’re trying to fix certain types of internet connection issues. It can also help keep your web browsing more private, assuming you choose a service that doesn’t log your information, and it can even give you access to sites that your ISP has blocked. While it’s unlikely for most people, you may benefit from faster internet speeds after changing your DNS servers.