DNS

 DNS stands for Domain Name System. It is a decentralized naming system for computers, services, or other resources connected to the Internet or a private network. DNS is responsible for translating human-friendly domain names, such as www.example.com, into the corresponding IP addresses that computers use to identify and communicate with each other.

When you type a domain name into your web browser, your computer turns to a DNS resolver (usually from your ISP or a third-party DNS service) to obtain the corresponding IP address. The resolver then queries DNS servers to find the IP address associated with the domain name. DNS servers store and distribute the mappings of domain names to IP addresses for the entire Internet.

The DNS system operates with a hierarchical structure. At the top level are root servers that provide information about top-level domains (TLDs) such as .com, .org, .net, and country-specific TLDs such as .us, .uk, and so on. Below the TLDs, there are authoritative name servers that store information about specific domain names and their IP addresses.

When a DNS resolver receives a query for a domain name, it traverses the DNS hierarchy, starting with the root servers and working down to the authoritative name servers responsible for that domain. The resolver stores the received IP address for a period of time to speed up subsequent queries for the same domain name.

DNS is critical to the functioning of the Internet because it allows users to access websites and services through memorable domain names without having to remember complex IP addresses. It also enables services such as emailing, FTP (File Transfer Protocol), and other network applications that rely on domain names for communication.