Read Book section 4.4: "Case study: The Internet Domain Name System (DNS)".
After you've read that section, you should understand DNS to the extent that you can answer Question 1 from our 2015 Quiz (solution). If you've read the section, but are unable to answer the question, please post on Piazza! We'll help you out.
As you read, think about the following:
Question for Recitation
Before you come to this recitation, write up (on paper) a brief answer to the following (really—we don't need more than a sentence or so for each question):