Devices in computing

Devices in computing

1. Storage

   • Storage devices store data 
   • DVD
     • The DVD has a similar spiral inside to the CD.However,this has more storage in it and can hold larger bits of data before the spiral is cut off.
   • CD
     • Stores information that can be accessed when put into a computer, CD player or radio.
   • Hard drive
     • A hard drive can store lots of data in a device.It does this by arranging the data in circular paths called tracks.The tracks are broken into smaller sections called sectors.The hard drive has a map of used sectors and unused sectors.When a computer wants new information to be stored,the map locates unused sectors and programmes the information to go to the selected sector.
   • USB stick
     • Like a CD,USB sticks are used for storage,to back up data and to transfer files onto different devices.However,they have 1000 times more capacity and are more transportable
   • MP3 player
     • When the music was transferred into the MP3 player,the device transfers all the sounds it can hear and then turns them into a number.Once the music is selected to be played,it transfers back from the numbers into the sounds and plays to the person using it.

2. Output

   • An output device gives something out to the user
   • Projector
     • There is a bright light that shines through a small LCD lens.This then projects a bigger,magnified image onto a wall or screen.
   • Headphones
     • From the computer,the sound travels through the wire and into the ear part.
   • Printer
     • Once a document has been sent to the printer,lots of tiny guns inside are used to fire tiny dots at the paper to make a picture.These dots are not visible to the human eye as they are so small
   • Ticket machine
     • To begin the system,customers pay money or scan their card into the machine and use a touchscreen to select their ticket destination.Once the money has been taken in,the information from the ticket is processed and it comes out with the tickets with the correct information.
   • Television
     • The flow of information about the channel that is going to be watched goes through the TV antenna and transmits onto the TV screen.The screen produces images by having tiny dots appear on the screen.To a human,these come out as full images.
   • Monitor
     • A monitor is an output device as it displays information that has been selected by an input device (Keyboard/mouse).It provides instant feedback by showing graphics and text.

3. Input

   • An input device is used by someone to give in something
   • Keyboard
     • The keys on the keyboard are pressed and sends the letter/number/symbol to the monitor
   • Mouse
     • To select things on a computer,the mouse uses a light source and a light detector to detect movement when the mouse is on a surface.
   • Scanner
     • Once the document is placed to be scanned,the scanner then sends instructions to the logic board.After it has chosen what speed to scan the document,a source of light shines through the document and it begins scanning the paper.The image is reflected to the scanner lens and then scans the document.
   • Microphone
     • A microphone is a device that converts energy from one form to another.They convert sound waves to audio signals.When the flow of information (Sound waves) goes through the microphone,it hits the diaphragm which vibrates.
   • Game controller
   • Television remote
     • The buttons on the remote are pressed by the user.The flow of information is then sent to the television (they are connected as the remote is wireless)
   • TouchScreen
     • The way you touch a touch screen device is called the resistive system.There are two layers:A normal glass panel with a sheet over it and a resistive metallic layer.They are held apart by spacers and a scratch-proof screen on top.Whilst the device is in use,electrical currents run through the screens.When the top screen is pressed,the two layers meet at that point.
   • JoyStick
     • There are certain wires for certain directions inside the joystick.When the user wants to move it a certain way,an electric charge is sent to the wire for that direction.

4. Processing

   • CPU (in a computer)
     • A CPU processes information and performs instructions on almost every computer.They run computer programmes and can cycle up to a billion times a second.This makes them efficient and a good aspect to have in a computer.They have separate modules that perform instructions for them
   • GPU (In a computer)
     • A CPU and a GPU have a similar processing system.However,this graphic card is designed specifically to perform mathematical and geometric problems and solve them.It uses special programming to help it analyze data