The Internet is a global system of interconnected computer networks that use the standard Internet protocol suite (TCP/IP) to serve billions of users worldwide.
In Simple Words, It is Network of Networks connecting All Kinds of Private, Government, Military, Academic, Public and All other.Typical users use Internet from LAN method.
LAN (Local Area Network) is a method of Networking which is basic and most popular, easy and cheapest schema.If, you know some basic about Internet. You must be familiar with term LAN (Local Area Network). Basic concept of LAN is as below:
You buy a Broadband Connection from your ISP (Internet Service Provider). In case of Nepal, Nepal Telecom, UTL and some other private companies,
In case of India Airtel, MTNL, VSNL, Sify or other Companies provide Internet service.
Then their Support Engineer visit your home and place a small device known as Modem or Router whatever you want to name. The word Modem is combined name of Modulator-Demodulator. This device converts Digital Signals to Electrical and vise-varsa.
So that Electric Signals flowing through Land Line cables are converted into Digital Signals so that Computers can understand them and once again The Requests from Computer are converted to Electrical Signals.
A Basic Diagram of How Modem work is:
Then there is one or multiple output port(s) on the back of your Modem and you connect Ethernet Cable with RJ45 Jack to your Ethernet Card (also known as Lan Card) on the CPU Box of your Computer or Laptop.
There are so much advance protocols and systems working behind this simple Logic and Process. Which I don’t want to discuss inside this topic. We will discuss that sometime later.