1. How does the Internet work?

The internet is a global network of interconnected computers and devices that communicate using standardized protocols. It enables data transfer, communication, and services like websites, emails, and streaming.

Key Concepts:

• Packets & Data Transfer: Data is broken into packets and transmitted over networks.
• Protocols: Standard rules for communication (TCP/IP, HTTP, HTTPS, FTP, etc.).
• Internet Service Providers (ISPs): Companies that provide access to the internet.
• Client-Server Model: Clients (browsers, mobile apps) request data from servers (websites, APIs).
• Routing & IP Addresses: Data is sent between devices using unique IP addresses.
• Subnetworks & Autonomous Systems: The internet is structured into networks managed by ISPs and organizations.

📖 Related Resources:

• How the Internet Works – FreeCodeCamp
• CS50 Lecture on Internet

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2. What is HTTP?

HTTP (HyperText Transfer Protocol) is the foundation of communication on the web. It defines how requests and responses are sent between clients (browsers) and servers.

Key Concepts:

• HTTP Request-Response Cycle: Clients send requests; servers respond with data.
• HTTP Methods:
  • GET: Retrieve data.
  • POST: Send data.
  • PUT: Update data.
  • DELETE: Remove data.
• Status Codes:
  • 200 OK: Successful response.
  • 404 Not Found: Resource not available.
  • 500 Internal Server Error: Server-side issue.
• Headers & Body: Metadata and content exchanged in requests and responses.
• Connectionless & Stateless: Each request is independent; servers don’t retain client state.

📖 Related Resources:

• MDN Web Docs on HTTP
• HTTP Explained – GeeksforGeeks

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3. What is a Domain Name?

A domain name is a human-readable address used to access websites. It maps to an IP address using the Domain Name System (DNS).

Key Concepts:

• Structure:
  • www.example.com
    • www: Subdomain.
    • example: Domain name.
    • .com: Top-Level Domain (TLD).
• Domain Registrars: Companies that sell domain names (GoDaddy, Namecheap, Google Domains).
• DNS Resolution: Converts domain names into IP addresses.
• Types of Domains:
  • TLD (Top-Level Domains): .com, .org, .net, etc.
  • ccTLD (Country Code TLD): .us, .in, .uk, etc.
  • Subdomains: blog.example.com, shop.example.com.

📖 Related Resources:

• ICANN - Domain Names
• What is a Domain Name? – Namecheap

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4. What is Hosting?

Web hosting is the service of storing and serving website files on the internet. Hosting providers offer servers and infrastructure to keep websites online.

Key Concepts:

• Types of Hosting:
  • Shared Hosting: Multiple websites on a single server.
  • VPS Hosting: Virtualized private resources on a shared server.
  • Dedicated Hosting: A full server dedicated to one website.
  • Cloud Hosting: Websites hosted on a network of virtual servers.
  • Managed Hosting: Hosting providers manage server maintenance.
• CDN (Content Delivery Network): Improves performance by caching content globally.
• SSL (Secure Sockets Layer): Encrypts communication for security.

📖 Related Resources:

• Web Hosting Guide – Hostinger
• Cloud Hosting Explained – AWS

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5. DNS and How It Works?

The Domain Name System (DNS) is a hierarchical system that translates domain names into IP addresses.

Key Concepts:

• DNS Query Process:
  1. User enters www.example.com in a browser.
  2. The browser asks the recursive DNS resolver for the IP address.
  3. The resolver queries the Root DNS Server.
  4. The Root Server directs it to the TLD Name Server (.com server).
  5. The TLD server directs it to the Authoritative Name Server for example.com.
  6. The resolver fetches and returns the IP address to the browser.
• Types of DNS Records:
  • A Record: Maps domain to IPv4 address.
  • AAAA Record: Maps domain to IPv6 address.
  • CNAME Record: Alias for another domain.
  • MX Record: Mail server mapping.
• DNS Caching: Speeds up resolution by storing recent queries.

📖 Related Resources:

• Cloudflare DNS Guide
• How DNS Works – MDN

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6. Browsers and How They Work?

Web browsers are software applications that retrieve, interpret, and display web pages.

Key Concepts:

• Rendering Engine: Converts HTML, CSS, and JavaScript into a visual page.
  • Chrome: Blink.
  • Firefox: Gecko.
  • Safari: WebKit.
• Steps in Page Rendering:
  1. Parsing HTML: Creates a DOM (Document Object Model).
  2. Parsing CSS: Creates a CSSOM (CSS Object Model).
  3. Render Tree Construction: Combines DOM & CSSOM.
  4. Layout & Painting: Determines positions & renders content.
  5. Compositing: Combines elements into the final page.
• JavaScript Engine:
  • Executes JavaScript code.
  • Uses Just-In-Time (JIT) Compilation for performance.
• Browser Components:
  • UI Layer: Address bar, tabs, navigation buttons.
  • Networking: Manages HTTP requests.
  • Storage: Cookies, LocalStorage, IndexedDB.

📖 Related Resources:

• Inside a Modern Browser – Google Developers
• MDN Guide on Browsers