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What is an IP Address? — The Identity of Every Device

Learn what an IP address is, why it was created, how it works, and the differences between IPv4, IPv6, public, and private IPs.

🌐 What is an IP Address?

An IP address (Internet Protocol address) is like the home address of your device on a network.
It helps computers, phones, and servers find and communicate with each other over the internet.

Whenever you visit a website, send an email, or watch a video —
your device and the server use IP addresses to locate and connect to each other.


🧩 Why IP Addresses Were Created

In the early days of networking, computers needed a way to identify and talk to one another.

Just like:

  • Your phone number helps people call you
  • Your home address helps people send you mail

An IP address helps computers send data to the right destination.

Without IP addresses, the internet wouldn’t know where to deliver your requests or responses.


🧠 How IP Addresses Work

Every time you connect to the internet:

  1. Your Internet Service Provider (ISP) gives your device an IP address.
  2. When you open a website (e.g., www.google.com), your system uses DNS (Domain Name System) to find the IP address of Google’s server.
  3. Then your browser connects to that IP, and data starts flowing between the two devices.

Example:

Here, 142.250.183.14 is the IP address of a Google server.


🧮 Types of IP Addresses

There are two main types of IP addresses based on how they are used.

TypeDescriptionExample
Public IPVisible on the internet; assigned by your ISP49.205.120.15
Private IPUsed inside your home or company network192.168.0.1

Public IP is like your house’s main address.
Private IP is like room numbers inside the house.


🌎 Public vs Private IP

FeaturePublic IPPrivate IP
VisibilitySeen by everyone on the internetSeen only inside local network
Given ByInternet Service Provider (ISP)Router or network admin
Example Range8.8.8.8, 49.205.120.15192.168.x.x, 10.x.x.x, 172.16.x.x
Use CaseWebsite hosting, remote accessHome Wi-Fi, internal communication

🔢 Versions of IP Addresses

There are two versions of IP currently in use — IPv4 and IPv6.


🌍 IPv4 (Internet Protocol Version 4)

  • Created in 1983
  • Uses 32-bit addresses
  • Example: 192.168.1.1
  • Total possible addresses: 4.3 billion

Since the internet grew fast, IPv4 started running out of unique addresses — that’s why IPv6 was created.


🌐 IPv6 (Internet Protocol Version 6)

  • Introduced in 1998
  • Uses 128-bit addresses
  • Example: 2401:4900:1f36:abc1::10
  • Total possible addresses: 340 undecillion (that’s 340 with 36 zeros!)

IPv6 solves the shortage problem and adds features like:

  • Better security
  • Faster routing
  • Built-in auto-configuration

🧭 Static vs Dynamic IP

TypeDescriptionExample Use
Static IPFixed and doesn’t changeServers, hosting websites
Dynamic IPChanges every time you connectHome or mobile networks

Your ISP usually gives you a dynamic IP, but servers or businesses often use static IPs so that their address stays the same.


🕸️ How IPs Work in a Network

Let’s take a simple home Wi-Fi example:

DevicePrivate IPInternet Access
Laptop192.168.0.10
Mobile192.168.0.11
Router192.168.0.1✅ (has a Public IP too)

Your router acts like a translator between private and public networks — using something called NAT (Network Address Translation).


🔐 Bonus: IPv4 Address Classes

ClassRangeUsage
A1.0.0.0 – 126.255.255.255Large networks
B128.0.0.0 – 191.255.255.255Medium networks
C192.0.0.0 – 223.255.255.255Small networks
D224.0.0.0 – 239.255.255.255Multicasting
E240.0.0.0 – 255.255.255.255Research/testing

🧾 Summary

  • IP (Internet Protocol) address = unique number that identifies a device on a network.
  • Public IPs connect you to the internet; Private IPs connect local devices.
  • Two versions exist: IPv4 (old, limited) and IPv6 (new, vast).
  • IPs can be static (fixed) or dynamic (changes automatically).
  • Without IP addresses, the internet simply cannot function — it’s how devices find and talk to each other.

🏁 In short:

An IP address is the digital identity of every device. It’s what makes the global internet work — connecting billions of computers, servers, and people every second.

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