What is Internet?

What is internet?

The Internet is a global network of interconnected computers and devices that communicate with each other using standardized protocols. It allows the sharing of information, resources, and services worldwide.

इंटरनेट एक वैश्विक नेटवर्क है जो कंप्यूटरों और उपकरणों को मानक प्रोटोकॉल के माध्यम से आपस में जोड़ता है। यह दुनिया भर में सूचना, संसाधनों और सेवाओं के आदान-प्रदान की सुविधा प्रदान करता है।

Key Concepts:

1. Network of Networks
   The Internet is not a single entity but a vast collection of smaller networks (like ISP networks, corporate networks, etc.) linked together.

इंटरनेट कोई एक इकाई नहीं है, बल्कि छोटे नेटवर्कों (जैसे ISP, कॉर्पोरेट नेटवर्क) का एक विशाल जाल है।

1. Protocols
   Computers on the Internet follow rules called protocols to communicate. The most important is TCP/IP (Transmission Control Protocol/Internet Protocol), which ensures data is properly addressed, transmitted, and received.

2. Key Services

   • World Wide Web (WWW) – Web pages and sites accessed via browsers (HTTP/HTTPS).

   • Email – Electronic mail (SMTP, IMAP, POP3).

   • File Transfer – FTP, cloud storage.

   • Instant Messaging & VoIP – WhatsApp, Zoom, Skype.

   • Streaming – Video, audio, and gaming services.

3. Infrastructure

   • Physical cables (fiber optics, copper), satellites, wireless towers.

   • Routers, switches, servers, data centers.

   • ISP (Internet Service Provider) – Companies that provide access to the Internet.

4. Addressing System

   • IP Address – Unique numerical label for each device (e.g., 192.0.2.1 or IPv6 2001:db8::).

   • Domain Name System (DNS) – Translates human-friendly names (like google.com) to IP addresses.

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How It Works:

1. You request a website by typing a URL.

2. DNS finds the IP address of that site’s server.

3. Your request travels via your ISP, through multiple routers, to the destination server.

4. The server sends back the web page data in packets.

5. Your device reassembles packets and displays the page.

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Brief History:

• 1960s – Early concepts in US military/research (ARPANET).

• 1980s – TCP/IP adopted; NSFNET expands academic use.

• 1990s – World Wide Web invented by Tim Berners-Lee; commercialization begins.

• 2000s–Present – Broadband, mobile Internet, social media, cloud computing, IoT.

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Importance:

• Revolutionized communication, education, business, and entertainment.

• Enables global collaboration and access to information.

• Raises issues like privacy, security, misinformation, and digital divides.