I was looking for Tier 1 helpdesk. An ideal answer would be: "DNS is how the computers translate names to IP addresses. If I'm having trouble reaching a resource by name but I can reach it by IP, I'll use nslookup to see what DNS server it's using, and see if there's a problem with the answer I'm getting. I sometimes use the host file to troubleshoot DNS problems, or ipconfig /flushdns." Bonus points if they talk about types of records, or how caching works.