What is a domain name?

A domain name is a human-readable name for a resource on the internet, used instead of an IP address, that indicates how to find a site or service.

In simpler terms: a domain name is the name of a site that a person types in.

---

#Why a domain name is needed

Computers work with IP addresses, for example:

93.184.216.34

Such addresses are inconvenient for people, so names are used instead:

• google.com
• github.com
• example.org

A domain name makes the internet convenient for people, while DNS is what turns it into an IP address.

---

#How a domain name is used

When you type in the browser:

example.com

the following happens:

1. the browser takes the domain name
2. it finds out the IP address through DNS
3. it connects to the server by IP

The domain name itself is not a server and not a site, it is a pointer used to find them.

---

#What a domain name consists of

Take this example:

www.example.com

#1. Top-level domain (TLD)

.com

• indicates the domain zone
• examples: .com, .ua, .org, .net, and others

---

#2. Second-level domain

example

• the site's main name
• most often the name of a company or project

---

#3. Subdomain (optional)

www

• used to separate services
• can be: api.example.com, mail.example.com

---

#Important point for an interview

• a domain name is not the same as an IP address
• one domain can point to:
  • one IP
  • several IPs (load balancing)
• the IP can change while the domain name stays the same

---

#Real-life example

A domain name is like:

• a person's name in a phone book
• you know the name, but the number can change

DNS is the phone book itself.

---

#Short interview answer

Remember this formulation:

A domain name is a character-based, human-friendly name for a resource on the internet that DNS translates into an IP address and that is used to access sites and services.