DNS, which stands for Domain Name System, functions as an IP address translation to website domain names. In fact, thanks to the DNS you can enter www.borderlessinternet.com in your browser's address bar to access the our website, not a lot of numbers and dots, which would be really difficult for humans to remember.
There are two ways to access a page on the Internet: You can type domain name i.e. www.hyas.com into your browser's address bar or type the IP address of the webserver which hosts the website you are trying to reach. Gladly, you don't need to enter a sequence of numbers in the browser. Again, that would be hard to remember. Gladly, DNS does all the hard work. It translates the words that make up the URL to the IP address of the website you are trying to reach. Each server has a unique IP address, so each domain leads to a unique IP. Therefore, you can not have two different sites with similar URLs. Otherwise, several different addresses could refer you to the same site.
A good analogy is to think of DNS as the phone book for the Internet. Without DNS, the Internet wouldn't work. There is an organization responsible for assigning domain names to IP addresses worldwide. It is ICANN (acronym for Internet Corporation for Assigned Names and Numbers), a nonprofit organization that tries to keep all registered websites running on the Internet.