What is a network? Most of us imagine internet whenever we hear this word.
Actually internet is just a form of network.
When two or more devices are connected to each other, in general terms we can call it a Network.
If the devices are computers, we will call it Computer Network.
Why we do it? - The main purpose of making a Computer-Network is to share data.
- We can share a single device from multiple PCs if the device and PCs are running under the same network.
- To share information through e-mailing, IM, chatting, tele and video conferencing.
- The largest network is internet.
On internet, a server stores and provides data to the us and we can upload, download, browse and share data with internet.
- Users under the same network can run or share the same application software from multiple PCs.
- Maintaining security.
- Speeding up the flow of data.
Types: Depending on the connection method Computer Networks are of two types; one is Wired Connection and another is Wireless Connection.
Depending on the area coverage Computer Networks can be of many types like, LAN, WAN, MAN, PAN, CAN, VPN etc.
Depending on the functional relationships Networking can be classified in active networking, client-server and peer-to-peer (work-group) architecture etc.
Depending on Topology a network can be classified in Bus (aka Backbone Networking), Star, Ring, Mesh, Hybrid (HUB+Bus), Star-Bus, Star-Ring etc.
What do we need to create it?

• Two or more PCs.
  
• Networking cables and devices e.
  g.
  LAN cards (for Wired Connection).
  
• Wireless Networking Devices e.
  g.
  Bluetooth or Infrared devices.