end of year 10 computing exam

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  • Created by: loupardoe
  • Created on: 04-07-16 17:13

input and output devices

input devices

  • keyboard- used for data entry into a computer
  • mouse- controls a pointer on screen that can be opened, dragged or controlled by clicking buttons on the mouse
  • touch screen- allows the user to interact directly with icons or an on-screen keyboard to control the device
  • microphone- uses voice input for communication or to control the device
  • camera- captures images or video
  • bar code scanner- reads light reflected back from a pattern of thin and thick lines that represent a product code or other identification number
  • RFID reader- reads data from an electronic version of a bar code; does not require line of sight; used in shops to identify products, in airports to track luggage, to tag animals, to collect payments automatically in toll booths, to access car parks
  • sensor- detects physical conditions and automatically collects data
  • eye types- can be used by people with limited physical mobility; camera tracks the movement of the user's eye and can detect which key the user is looking at, a slow blink is used to select the key to type commands into a computer system
  • foot mouse- can be used by people with limited hand movement; track ball device that can be operated with the foot
  • puff-**** switch- can be used by people with severely limited physical mobility by blowing or ****ing into a small tube
  • braille keyboard- can be used by people with visual impairments to type text and commands into a computer system using keys with embossed patterns that match the standard braille characters

output devices

  • monitor- displays text, images and video
  • printer- produces hard copy on paper
  • plotter- reproduces large scale engineering or architectural drawings
  • speakers- produce sound output
  • actuators- create physical movements in response to a computer command to control aeroplanes, wheelchairs and robots

network topologies

bus

  • computers and other devices are attached to a single backbone
  • terminator attached at each end to prevent reflection of signals
  • signals travel in either direction
  • easy to set up
  • cheap
  • problems with the backbone can bring the whole network down
  • limited distance can be covered
  • many data collisions slow the network down

star

  • client machines are connected to a central switch or hub which is usually connected to one or more servers
  • signals travel in either direction
  • robust- problems with a connection do not affect the whole network
  • fewer data collisions than bus so faster
  • needs more expertise to maintain
  • can be expensive to set up
  • more building work involved
  • more network hardware and software needed

ring

  • data passes through each node carried in data units called tokens
  • traffic is one way which prevents collisions
  • very fast- no collisions
  • problems with the backbone can bring the whole network down
  • data passes through every node- this makes the network vulnerable to malfunctions

client server network

  • one or more servers provide services to many client machines where the users work
  • servers are computers that are set up to handle network functions
  • may be many on a network
  • typically high…

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