host:tldr:e6742

The command "host ${domain} ${8-8-8-8}" is used to query the DNS (Domain Name System) server for information about a specific domain.

Here's a breakdown of the command:

• "host" is the command-line utility used to perform DNS lookups and query DNS servers.
• "${domain}" is a placeholder for the actual domain name you want to query. You would replace it with the desired domain name, for example, "example.com".
• "${8-8-8-8}" is another placeholder for the IP address of a DNS server. In this case, it represents the IP address of Google's public DNS server, which is commonly used. The IP address "8.8.8.8" corresponds to the primary Google DNS server.

So, when you run this command, it will send a DNS query to the DNS server specified (in this case, Google's DNS server) asking for information about the provided domain name.