Anyone who uses the Internet uses the Domain Name System, or DNS, even without knowing it. DNS is the protocol in a set of standards which computers exchange data on the Internet and many private networks, known as TCP / IP. This system is responsible to replace the user-friendly domain names like "" into an Internet Protocol (IP), such as which computers use to identify each other on the network.

Computers and other network devices on the Internet using the IP Address to redirect the request to the page you are trying to reach. This is similar to dialing a phone number to connect with another person you must enter a number or select it from the address book. With DNS do not have to keep your own books of IP addresses. The DNS server acts as the address book. Just connect to it. These servers have a very large database of domain names that are mapped to an IP address.

You can always skip the DNS lookup typing directly in the browser. Entering direct IP address will be much more problematic to remember a user friendly than the words "". In addition, the Web site, your IP address may change over time, and some sites may condemn a number of IP addresses from one domain.

But how does the computer know which DNS server to use? Typically, when you connect to your home network Internet service provider (ISP) or a WiFi network, modem or router that assigns address of the computer on the network, it also sends an important network configuration information to a computer or mobile device. The configuration includes one or more DNS servers that your device should use when translating DNS names to the IP address.

In the world there are many billions of IP addresses that are used by computers or network equipment to connect to the Internet. DNS servers convert the billions of requests for processing a good domain name into an IP address.

Each device hooked up to the Internet has a unique IP address. Addresses are available in two standard IPv4 and IPv6. IP address management is the Internet Assigned Numbers Authority (IANA).

The IP address of the IPv4 standard consists of four numbers separated by a dot.

However, we have a standard IPv6 eight hexadecimal numbers (Base-16) separated by colons. IPv6 is not long ago introduced standard and is relatively less used than its predecessor.

Anyone know a domain name as text divided by dots. The last word in the domain name is the top-level domain (top-level domain). These domains are controlled by the IANA and called the root zone database (Root Zone Database "). Here are examples of top-level domains.

COM – for commercial sites

NET – for networking sites

ORG – non-profit organizations

EDU – limited to schools

MIL – Limited to the military

GOV – Designed for government

PL – Domain designed for parties Polish

The domain name every combination of words and dots must be delivered at the end of the top-level domain. Each level refers to a server or group of servers that manage the domain level. For example, the domain "" is a two-level domain Domain UK top-level domain. An organization can have a hierarchy of subdomains. For example, "" sub-domain is a domain PL.

All domain names must be unique. Therefore, the authorized domain registrars register new domains in one or more domains of the first level in the InterNIC, services ICANN, which enforces the uniqueness of domain names on the Internet. Each domain is an integral part of a central database of domain registration, known as WHOIS.