TrainWithShubham · dhananjaylavate · May 31, 2026 · May 31, 2026 · May 31, 2026 · May 31, 2026
diff --git a/.github/instructions/md-formatting.instructions.md b/.github/instructions/md-formatting.instructions.md
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+---
+name: md-formatting
+description: "Apply consistent Markdown formatting to all .md files in this repository, with commands formatted as code and emojis used for emphasis and clarity."
+applyTo: "**/*.md"
+---
+
+Use this instruction for every Markdown file in the repository.
+
+- Format commands and CLI examples using inline backticks for commands (`git status`) and fenced code blocks for longer snippets.
+- Use headings, lists, and bold text to structure content clearly.
+- Add emojis for emphasis and readability, for example:
+  - ✅ for success or recommended actions
+  - ⚠️ for warnings and caveats
+  - 💡 for tips and notes
+  - 🔧 for technical steps
+- Keep prose clear and concise, with proper sentence spacing.
+- Avoid raw unformatted command text in paragraphs; commands should always be in Markdown code formatting.
+- Ensure generated or updated Markdown follows the repo's consistent style across `README.md`, lesson notes, and other `.md` files.
diff --git a/2026/day-14/OSI Models 2.jpg b/2026/day-14/OSI Models 2.jpg
diff --git a/2026/day-14/OSI Models.jpg b/2026/day-14/OSI Models.jpg
diff --git a/2026/day-14/day-14-networking1.md b/2026/day-14/day-14-networking1.md
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+# Day 14 - Networking Basics and OSI Layer
+
+# 🌐 1. What a Network Actually Is
+
+A network is simply:
+
+> 🧠 A group of devices connected so they can talk to each other.
+
+## 📌 Examples:
+
+- Your laptop ↔ router  
+- Your phone ↔ Wi-Fi  
+- Servers ↔ other servers  
+- Your device ↔ Google  
+
+## 🔗 They can be connected using:
+
+- 🔌 Cables (Ethernet)  
+- 📶 Wi-Fi (wireless signals)  
+- ☁️ Virtual links (cloud networks like AWS)  
+
+---
+
+## 2. The OSI Model (Open Systems Interconnection Model)
+
+**The OSI Model (Open Systems Interconnection Model) is a conceptual framework used to understand how data travels from one computer to another over a network**
+
+**It breaks the entire networking process into 7 separate layers, where each layer has a specific job.**
+
+- Application
+- Presentation
+- Session
+- Transport
+- Network
+- Data Link
+- Physical
+
+# 🌐 What Happens When You Open Google (OSI Model Real-World Example)
+
+This document explains what happens behind the scenes when you type `www.google.com` in your browser and press Enter, mapped to the **OSI Model (7 Layers)**.
+
+# 🧠 Scenario Overview
+
+When you open Google, your computer performs multiple networking steps in milliseconds to fetch and display the webpage.
+
+# 🌐 Step-by-Step OSI Model Breakdown
+
+---
+
+## 7. Application Layer (Layer 7)
+
+You interact with the browser (Chrome, Edge, Firefox).
+
+- You type: `www.google.com`
+- Browser understands user request
+- Creates an HTTP/HTTPS request
+
+👉 Meaning:
+You are requesting a webpage.
+
+---
+
+## 6. Presentation Layer (Layer 6)
+
+Data is prepared for secure transmission.
+
+- Data formatting happens
+- Encryption is applied using **HTTPS (TLS/SSL)**
+
+👉 Meaning:
+Data is encrypted so no one can read it during transmission.
+
+---
+
+## 5. Session Layer (Layer 5)
+
+A communication session is established.
+
+- Connection between your computer and server is created
+- Session is maintained while browsing
+
+👉 Meaning:
+Keeps communication active until you close the browser/tab.
+
+---
+
+## 4. Transport Layer (Layer 4)
+
+Ensures reliable data delivery.
+
+- Data is broken into segments
+- TCP protocol is used (reliable delivery)
+- Lost packets are retransmitted
+
+👉 Meaning:
+Ensures all data arrives correctly and in order.
+
+---
+
+## 3. Network Layer (Layer 3)
+
+Handles routing and IP addressing.
+
+- DNS converts `google.com` → IP address (e.g., 142.250.x.x)
+- Routers decide best path for data packets
+
+👉 Meaning:
+Finds the correct destination across the internet.
+
+---
+
+## 2. Data Link Layer (Layer 2)
+
+Handles local network communication.
+
+- Data is framed
+- MAC addresses are used
+- Communication between device and router
+
+👉 Meaning:
+Delivers data within your local network (Wi-Fi/Ethernet).
+
+---
+
+## 1. Physical Layer (Layer 1)
+
+Actual transmission of data happens.
+
+- Data becomes electrical signals / radio waves / light signals
+- Sent via cables, fiber optics, or Wi-Fi
+
+👉 Meaning:
+Raw 0s and 1s travel through physical medium.
+
+---
+
+# 🌍 Server Side (Google)
+
+The request reaches Google servers  
+(operated by :contentReference[oaicite:0]{index=0})
+
+- Server processes your request
+- Generates response (HTML, CSS, JS)
+- Sends data back through the same layers in reverse
+
+---
+
+# 🔁 Reverse Process (Receiving Data)
+
+When response comes back:
+
+1. Physical signals → bits
+2. Data Link → frames processed
+3. Network → routing removed
+4. Transport → segments reassembled (TCP)
+5. Session → connection maintained
+6. Presentation → decrypted (HTTPS)
+7. Application → browser renders page
+
+---
+
+# 📦 Final Output
+
+Your browser displays:
+
+👉 Google homepage
+
+---
+
+# 🧩 Simple Summary
+
+Opening Google involves:
+
+- Request creation (Application Layer)
+- Encryption (Presentation Layer)
+- Session establishment (Session Layer)
+- Reliable transfer via TCP (Transport Layer)
+- Routing via IP (Network Layer)
+- Local delivery via MAC/Wi-Fi (Data Link Layer)
+- Physical transmission via signals (Physical Layer)
+
+---
+
+# 💡 One-Line Understanding
+
+> Opening Google is your computer sending a structured, encrypted request through 7 networking layers, and receiving a response that is rebuilt into a webpage.
+
+---
+
+# 🚀 Key Takeaway
+
+The OSI model helps us understand:
+
+- How data travels across networks
+- How different devices communicate
+- How complex networking is broken into simple layers
+---
+
+# 💡 Key Insight
+
+> `curl https://www.google.com` is not “just a command” — it is a full OSI stack in action, from Application layer down to Physical transmission and back up again.
+
+---