Introduction to the Internet

The Internet is the invisible web of connections that powers almost everything we do — from loading a webpage to sending a message across the globe. It’s not a single machine or network but a massive system of interconnected computers communicating through agreed-upon rules called protocols.

What Is the Internet?

At its core, the Internet is a network of networks. Every device connected to it — whether it’s your phone, a data center, or a satellite — follows these same protocols to exchange information.

info

Many people confuse the Internet with the World Wide Web (WWW). The Internet is the infrastructure (the cables, routers, and data pathways), while the Web is a service built on top of it — using browsers and HTTP to access websites.

This diagram shows the typical journey of a web request. When you open a site, your device connects through your router, passes through your ISP, queries a DNS server to find the site’s location, and finally reaches the web server that sends the page back.

How the Internet Works

Simple View

When you type a URL like https://codeharborhub.github.io, your browser first asks a DNS server to find the matching IP address.
It then connects to that address using HTTP or HTTPS, downloads the data, and displays it as a webpage.

Technical View

1. The browser sends an HTTP request to the server.
2. The request is split into packets and routed through various networks using TCP/IP.
3. The server responds with an HTTP response, usually containing HTML, CSS, or JS files.
4. HTTPS adds a layer of encryption, ensuring data privacy during transmission.

A Simple HTTP Request in Action

Live Editor

function InternetExample() {
  return (
    <div style={{ textAlign: "center" }}>
      <h3>Browser Request Simulation</h3>
      <p>Client → DNS → Server → Response</p>
      <button onClick={() => alert("Response: 200 OK")}>Send Request</button>
    </div>
  );
}

Result

Loading...

When you click the button, imagine your browser requesting data from a remote server — and getting a “200 OK” response if everything works correctly.

Core Components of the Internet

Component	Role
Client	The end-user device (like a browser or mobile app) that requests data.
Server	The machine that processes requests and sends back responses.
DNS	Converts domain names (like codeharborhub.github.io) into IP addresses that computers understand.
ISP	Connects users to the global Internet infrastructure.
Router	Directs data packets between networks, ensuring they reach the right destination.

Understanding Data Transfer

The rate of data transfer (speed) can be described mathematically:

$$Speed = \frac{Data\ Size}{Time}$$

For example, downloading a 10 MB file in 5 seconds means:

$$Speed = \frac{10}{5} = 2\ \text{MB/s}$$

While this looks simple, real-world speeds depend on factors like bandwidth, latency, and network congestion.

The TCP/IP Model

The Internet runs on a layered system known as the TCP/IP model, which defines how data moves from one point to another.

Each layer has a specific job:

• Application Layer: Handles data for applications (HTTP, DNS, FTP).
• Transport Layer: Ensures reliable delivery (TCP, UDP).
• Internet Layer: Routes packets using IP addresses.
• Network Access Layer: Manages physical connections (Ethernet, Wi-Fi).

Key Takeaways

• The Internet is a global system that connects billions of devices.
• Communication happens through clients, servers, and routers using standard protocols.
• DNS resolves domain names, and TCP/IP ensures reliable data transfer.
• Security protocols like HTTPS protect your information online.