History of domain names

Let’s start with the definitions. A domain is the name of a website. When the Internet was first invented, domains did not exist. To connect to a computer, you needed to know its numerical identifier — an IP address. An IP address can often indicate the location from which a device is connected to the Internet. Since people found it difficult to remember long strings of numbers, text-based names were introduced instead. It works much like a phone contact list: you do not memorize every phone number, but instead save the name of the person or company associated with it. So, what exactly is a domain and a domain name?

Initially, all available names were stored in text files called etc/hosts. Anyone who owned a computer and wanted to assign a text name to it had to contact Stanford University (where the Internet was originally developed) and have the name added manually. This approach quickly became impractical as the network expanded and evolved. Scientists therefore sought a way to automate the process. This led to the creation of domain names — a system that is still used today.

Originally, there were seven domain zones:

.com — used by commercial organizations;

.org — used by cultural and charitable projects;

.net — used by network-related organizations;

.edu — used by educational institutions;

.gov — used by government agencies;

.mil — used by military organizations;

.arpa — used by network infrastructure and research systems.

The first domain in the .com zone was registered in January 1985. It is considered the most well-known international domain extension. Since 1997, users have no longer been able to register three-letter domain names in this zone. Another widely recognized domain is .org, which has traditionally been used by charitable organizations, cultural initiatives, and educational projects.

If we look deeper into the subject, we find that a domain name consists of several levels. A Fully Qualified Domain Name (FQDN) includes:

• Level 0 domain (not displayed);
• Level 1 domain (belongs to a thematic or geographic zone). Examples: .com, .edu, .org, .ua, .eu;
• Level 2, 3, 4, and higher-level domains (the unique name assigned to the website owner).

As a result, we get a complete domain name — the unique address of a website on the Internet.