What Is an IP Address? A Beginner’s Guide to IPv4 and IPv6

What Is an IP Address?

An IP address (Internet Protocol Address) is a unique identifier assigned to a device connected to a network. It allows devices to communicate with each other and exchange data over local networks and the Internet.

Think of an IP address as a home address. Just as a postal service needs an address to deliver a letter, computers need IP addresses to send and receive information.

Why Do We Need IP Addresses?

Without IP addresses, devices would not know where to send data.

For example, when you visit a website:

1. Your computer sends a request.
2. The request contains your IP address.
3. The website’s server receives the request.
4. The server sends the response back to your IP address.

This process happens within milliseconds.

How Does an IP Address Work?

When a device joins a network, it receives an IP address.

Example:

If Computer A wants to communicate with Computer B, it uses the destination IP address to ensure the data reaches the correct device.

Types of IP Addresses

IP addresses can be categorized into:

• Public IP Addresses
• Private IP Addresses
• Static IP Addresses
• Dynamic IP Addresses

Public vs Private IP Addresses

Public IP	Private IP
Accessible from the Internet	Used inside local networks
Assigned by an ISP	Assigned by routers
Must be globally unique	Can be reused in different networks

Examples of private IP ranges:

10.0.0.0 - 10.255.255.255

172.16.0.0 - 172.31.255.255

192.168.0.0 - 192.168.255.255

IPv4 Addresses

IPv4 is the fourth version of the Internet Protocol and remains the most widely used today.

Example:

192.168.1.100

IPv4 uses:

• 32-bit addresses
• Four decimal numbers
• Approximately 4.3 billion possible addresses

IPv6 Addresses

IPv6 was created to solve IPv4 address exhaustion.

Example:

2001:0db8:85a3:0000:0000:8a2e:0370:7334

IPv6 uses:

• 128-bit addresses
• Hexadecimal notation
• Nearly unlimited address space

How to Find Your IP Address

Windows

Open Command Prompt:

ipconfig

Linux

ip addr

Public IP

You can search:

What is my IP?

in your browser.

Conclusion

IP addresses are fundamental to network communication. Every device connected to a network requires an IP address to send and receive data. Understanding IP addressing, IPv4, and IPv6 is essential for networking, cybersecurity, and system administration.

IP Address Summary Worksheet