How do domain names relate to IP addresses?

Domain names are human-friendly identifiers that correspond to numerical IP addresses used by computers.

In the world of the internet, every device connected to the network is assigned a unique IP (Internet Protocol) address. This IP address, a series of numbers separated by periods (in IPv4) or colons (in IPv6), is used to identify and locate devices on the network. However, remembering and typing these numerical addresses can be quite challenging for humans. This is where domain names come into play.

Domain names are essentially the human-friendly versions of IP addresses. They are easier to remember and type than a string of numbers. For example, it's much simpler to remember 'www.google.com' than '172.217.14.238'. When you type a domain name into your web browser, a process called DNS (Domain Name System) lookup is initiated. The DNS is like the phonebook of the internet, translating human-friendly domain names into machine-friendly IP addresses.

The DNS lookup process involves several steps. First, your computer checks its local DNS cache, which stores information about recent visits to websites. If the IP address corresponding to the requested domain name is not found in the local cache, the request is sent to the ISP's (Internet Service Provider) DNS server. If the ISP's DNS server also doesn't have the information, the request is forwarded to the root DNS servers. These servers don't know the IP address either, but they can direct the request to the TLD (Top-Level Domain) servers, which hold information about domains under specific domain extensions like .com, .org, .net, etc. The TLD servers then direct the request to the authoritative DNS servers, which finally return the corresponding IP address to your computer. Once your computer receives the IP address, it can establish a connection with the server hosting the website and retrieve the web page.

In summary, domain names and IP addresses are two sides of the same coin. They both serve to identify and locate devices on the internet, but while IP addresses are designed for machines, domain names are designed for humans. The translation between the two is handled by the Domain Name System, ensuring that the internet remains user-friendly while still being efficiently navigable by computers.