Computer Networks

1. Router:  A way of dividing two networks up so info can be passed  from one network to another keeping the traffic separate. They control traffic and send messages between two networks. Message is either internal(for inside the house) or external(outside the house).
2. WIFI and Bluetooth: Wireless technologies used for transferring data between devices without the need for a physical connection or wiring. Bluetooth is used by mobile devices for transferring files. Bluetooth is an agreement between two devices and is organized by the devices itself whereas WIFI is organized by an actual system.
3. Small Network Setup: To set up a network with internet you need and ISP(Internet Service Provider) eg.Telecom who will give you a router. Use a browser to surf the internet. 
4. Advantages: You can share a resource across a network.  Disadvantages:  Viruses(designed to damage your system and prevented by anti-virus software) hacking files(prevented by firewall) inappropriate pop-ups(eg.porn), loss of resources(printers break down)
5. User IDs and Passwords: are used to divide information between people and authorize and control access to different resources.
6. Fax: A hard copy of print.Disadvantages: You can't control who picks up the fax at the other end. The sent fax could be waiting on the receivers tray until the receiver realises it. Email: a method of exchanging digital messages from an author to one or more recipients. CC means of interest but not to the target.  Tele/Video Conferencing: Conferencing is a group of people discussing things together with no need to physically make the journey to see them. Video conferencing means you can see content.
7. Local Area Network(LAN): A local network onsite. Wireless Local Area Network and Wide Area Network(WAN): A network on more than one site.
8. Differences between LAN,WLANs and WANs: To create a wireless LAN you need a access point that's linked to the LAN on site. For a WAN you need a router and an external internet line. A WLAN is there to service mobile phones. 
9. Intranets: An internal website used for managing resources and files internally. People are familiar with the interface. Internet: Offers services to the world advertising things such as yourself, your business etc.
10. Hub: A box that multi-broadcasts across a network. Bridge: Used to organise the LAN to maximize the sending of the signal in terms of its speed. Switch: Managers the traffic from a specific port to another. Proxy Server: Makes your connections to the world anoynomous. It manages the band width.
11. Confidentiality: Hacking means a firewall which means a legal guarantee of data and you must have a data.