Computer system

Computer system

1. Computer data Converter

   • Analogue signals
     • They are signals made by sound waves.
     • Types of Analogue
       • Microphones
       • Singing/ vocal voice
   • Digital Signals
     • The signals that are like number that only computer devices can read
       • Types of Digital
         • Computer
           • Mobile Phones
   • How does it work?
     • Analogue can be converted to digital.
       • With an ADC
         • Which stands for Analogue to Digital Converter
       • This is good because it allows a computer to read analogue data
       • This is how music is now created
         • From singing into a microphone and importimg the track to the computer
   • Digital signals can also be converted to Analogue signals
     • With a DAC
       • Which stands for Digital to Analogue Converter
         • From your music in your phone (As an example)
           • It is converted so that you can hear it through your phone speaker or earphone

2. Components of a computer system

   • Types of components
     • Hardware
       • They are things of a computer you can touch
         • For examples:
           • Mouse/Pointer
           • Keyboard
           • Monitor
     • Software
       • They are things inside a computer that you can not touch
         • For Examples:
           • Icons
           • Websites
           • CLI
             • Stands for Command Line Interface
     • CPU
       • Stands for Central Processing Units
         • It's the brain of the compurter
     • ROM/RAM
       • ROM: It stands for Read Only memory. It stores Data in a computer and the data is non-voluntary which means it will not be deleted after the device if turned off
       • RAM: It stands for Random Access memories. It stored data in a computer and the data is voluntary which means that the data will be lost after the device has been shut down
     • Inputs/Outputs
       • Input devices are things you insert in a device
         • Such as:
           • Memory Stick
           • Microphone
           • Keyboard
           • Scanner
       • Output Devices are things that are let out from a device
         • Such as:
           • Speakers
           • Monitors
           • Printer
           • Projector

3. Accessing stored Data

   • Serial/Sequential Access
     • It accesses stored data in a one by one squence
     • If you want to go in a specific part of a movie for example, with a Serial access you will have to rewind or fast-forward. you cant skip the scenes
   • Direct/Random Access
     • It means that you can access data anywhere any time. it has so squences
     • For example: On a DVD you can skips scenes without watching them.

4. Networks

   • LAN
   • WLAN
     • It stands for Wireless Local Access network
   • WAN