Domain Name System (DNS)

The Domain Name System (DNS) is a hierarchical and decentralized naming system for computers, services, or other resources connected to the Internet or a private network. It associates various information with domain names assigned to each of the associated entities. Most prominently, it translates domain names meaningful to humans into the numerical IP addresses needed for locating and identifying computer services and devices with the underlying network protocols. Due to the ubiquity of the internet, the DNS has become an essential component of the Internet infrastructure.

The internet is a vast network of computers and devices connected to each other. In order to communicate with each other, these computers and devices need to be able to identify each other. This is where the DNS comes in. DNS is like a phone book for the internet. When you want to visit a website, you type in the domain name of the website into your browser. The DNS then looks up the IP address of the website and directs your browser to the correct website.

DNS Structure

The DNS is a hierarchical structure, with the root at the top. The root is divided into several top-level domains (TLDs), such as .com, .net, and .org. Each TLD is divided into several second-level domains (SLDs), and so on. Each domain can be further divided into subdomains.

For example, the domain name www.example.com is composed of the following parts:

• The root domain is "."
• The top-level domain is ".com"
• The second-level domain is ".example"
• The subdomain is "www"