Internet revision

Internet revision

1. What is the internet?

   • A network of networks
   • This is connected by a common set of protocols
   • Used world wide

2. Digital and analogue

   • Computer use digital signals
   • Telephone systems use analogue signals
   • You have to use a modem to convert between the two.

3. File Types

   • Image file
     • JPEG
     • GIF
       • only 256 colours
     • PNG
   • audio file
     • MP3
   • Document file
     • PDF
       • Can be read on multiple devices
   • video file
     • MPEG

4. Router

   • Moves data packet along
   • Finds the fastest route

5. DNS server

   • Domain Name System server
     • from domain name
       • To IP addresses

6. HTML

   • Hyper Text Mark-up Language
   • Can be read by multiple web browsers