🍌 Domain vs IP 🍌

How Humans & Machines Identify Servers · DNS · Graduate Course

— The Banana Warehouse Analogy —

🍌

IP Address

GPS coordinates of the warehouse

📖

DNS

The phonebook that maps name → coords

🏪

Domain Name

The warehouse's brand name

Dimension	IP Address	Domain Name
Form	Numbers (e.g. 142.250.80.46)	Words (e.g. google.com)
Audience	Machines	Humans
Uniqueness	Globally unique	Globally unique (registered)
Mutability	May change (dynamic IP)	Stable, can point to new IPs
Structure	Flat numeric	Hierarchical (TLD → domain → sub)
Direct comms	Yes — used directly	No — must resolve via DNS first

One Domain → Many IPs

google.com resolves to different IPs for different users worldwide — this is load balancing. The same domain name distributes traffic across hundreds of servers.

google.com → 142.250.80.46 (US)
google.com → 203.208.43.1 (Asia)

Many Domains → One IP

A single server (one IP) can host multiple websites. The server reads the HTTP Host header to decide which site to serve — this is called virtual hosting.

siteA.com ─┐
siteB.com ─┼→ 192.168.1.1
siteC.com ─┘