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What is Wi-Fi? And How is it Different from the Internet?

 Wi-Fi is everywhere—in our homes, cafes, airports, and offices—but many people still confuse it with the internet itself. While they work together to bring you online access, Wi-Fi and the internet are not the same thing . One is a wireless connection technology, and the other is a vast global network. In this post, we’ll break down what Wi-Fi actually is, how it works, and how it's different from the internet—all in simple, easy-to-understand terms. If you've ever wondered why you have full Wi-Fi bars but no internet, this guide is for you. How Wi-Fi Works: The Local Wireless Connector Wi-Fi , short for Wireless Fidelity , is a wireless networking technology that lets devices connect to a local network without cables. It works through a Wi-Fi router , which sends out radio waves that your phone, laptop, or smart TV can detect and use to access the network. The router itself is usually connected to a modem , which brings in the internet from your Internet Service Provider (...

How the Internet Actually Works (Explained Simply)

The internet is a part of our daily lives—we use it to send messages, stream videos, buy products, and learn new things. But have you ever stopped to ask, how does the internet actually work ? Behind the scenes, an invisible web of computers, routers, cables, and protocols come together to deliver what you see on your screen in milliseconds. In this post, we’ll break it down in the simplest way possible, avoiding jargon and making it easy to follow, even if you’re not a tech expert. Get ready to understand the magic behind your browser!  The Backbone of the Internet: Servers, Clients, and Data Packets At its core, the internet is a global network of computers that communicate with each other. When you visit a website, your device acts as a client sending a request to a server . That server stores the website’s data and sends it back to you in small chunks called data packets . These packets are transmitted using a complex system of protocols , which are like rules that ensure e...

What Happens When You Type a URL and Hit Enter?

  DNS Resolution: Finding the Right Server The journey begins with DNS (Domain Name System) resolution . When you type a URL like www.example.com , your browser first checks its cache to see if it already knows the IP address. If not, it queries a DNS server—often provided by your ISP or a public DNS like Google’s 8.8.8.8. This server returns the IP address associated with the domain. Think of DNS as the internet’s phonebook—it translates human-readable domain names into machine-readable IP addresses. Without this translation, your browser wouldn’t know where to send your request. TCP Handshake and Establishing a Connection Once the IP address is known, your browser initiates a TCP (Transmission Control Protocol) connection. This involves a three-step handshake: The browser sends a SYN packet to the server. The server replies with a SYN-ACK. The browser completes the handshake with an ACK. Only after this secure connection is established can your browser start ...

How Neural Networks Learn: Activation Functions and Backpropagation

 Understanding how neural networks learn is essential to grasping the fundamentals of artificial intelligence and deep learning. At the heart of this process lie two critical components: activation functions and backpropagation . These elements work together to enable neural networks to model complex patterns, make accurate predictions, and continuously improve through training. In this post, we will explore the roles of activation functions and backpropagation, how they work, and why they are essential in the learning process of neural networks. The Role of Activation Functions Activation functions are mathematical equations that determine the output of a neural network node, or “neuron.” They decide whether a neuron should be activated or not by calculating a weighted sum and applying a transformation. Without activation functions, neural networks would simply behave like linear regression models, lacking the ability to model complex data relationships. One of the most common a...

How Firewalls Analyze and Filter Packets

 Firewalls are the digital bouncers of your network — deciding which traffic gets in, which gets blocked, and what needs further inspection. Whether you're using a personal computer, managing a business network, or securing cloud infrastructure, firewalls are essential to protect against unauthorized access and cyber threats. But how do firewalls actually work ? Let’s break down how they analyze and filter packets to keep your system safe. What Is a Firewall? A firewall is a security device (hardware or software) that monitors and controls incoming and outgoing network traffic based on predetermined rules. It acts as a barrier between a trusted internal network and an untrusted external network , like the internet. What Are Packets? Before diving into filtering, it’s important to understand what a packet is. A packet is a small chunk of data sent over a network. Each packet contains: Header – Metadata like source IP, destination IP, protocol, port number, etc. ...

TLS Handshake Explained Step-by-Step

 Every time you visit a secure website (like https://example.com ), your browser and the web server quietly perform a TLS handshake — a behind-the-scenes conversation that ensures your connection is private, secure, and authentic. TLS (Transport Layer Security) is the cryptographic protocol that powers HTTPS , email encryption , and VPN connections . Let’s break down exactly what happens during a TLS handshake, step-by-step. What Is a TLS Handshake? A TLS handshake is the process by which a client (like your browser) and a server: Agree on encryption methods Authenticate each other Exchange secret keys to start secure communication This all happens in just a few milliseconds, before any actual data (like a login form or webpage content) is exchanged. Why It Matters Without the TLS handshake, encrypted communication over the internet wouldn’t be possible. It protects against: Eavesdropping Tampering Impersonation Now, let’s walk through the steps. ...

Common Types of Cyber Attacks and How They Work

Cyber attacks have become an everyday threat in our connected world — targeting individuals, businesses, and governments alike. These digital assaults can steal sensitive data, lock you out of systems, or bring entire networks to a halt. Understanding how they work is the first step toward defending against them. Here’s a deep dive into the most common types of cyber attacks , how they operate, and what you can do to protect yourself. 1. Phishing Attacks What It Is: Phishing is a type of social engineering attack where attackers trick you into revealing personal information — like passwords or credit card numbers — by pretending to be someone you trust. How It Works: You get an email that looks legit (from your bank, a coworker, etc.) It includes a fake link or attachment Clicking it sends you to a fake login page or installs malware How to Protect: Don’t click suspicious links Use email filtering tools Enable multi-factor authentication (MFA) 2. Malware Attacks Wha...