> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://helpdesk.gbnetwork.com/sitemap.xml
> Use this file to discover available pages before exploring further.
> Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash).

# Types of DNS Lookups

| Types of DNS Lookups
> DNS is most commonly used by Web browsers, automatically converting Internet domain names to IP addresses.
Beside these forward lookups, the DNS is also used for:

* finding the correct servers to deliver Internet email
* reverse lookups that convert an IP address back to a domain name

The network requests supporting DNS lookups run over TCP and UDP, port 53 by default.