DNS servers _usually_ reply with information about a queried domain name or a host name. dig is a command-line tool that queries a given name server (or a preset one) for that information. For example `dig news.ycombinator.com` returns the IP address of HN, and `dig news.ycombinator.com @example.com` queries the example.com nameserver for that domain.

dns.toys runs a DNS server that dynamically returns answers such as times, currency information, etc (instead of domain name information) if you format your query right.

So for example, `dig mumbai.time @dns.toys` returns the time in Mumbai in a DNS TXT record instead of an IP address (or an NXDOMAIN response, saying the domain does not exists).

Play around with the `dig` command, it is an intuitive tool that you will eventually use if you are a CS or a related Freshman.