Computing Revision

Computing Revision

1. CPU

   • Central processing Point
   • Processes Data and instructions using the fetch decode cycle
   • CPU with a dual core processor will mean that Programs will load faster because 2 two processors will perform the fetch decode execute cycle at the same time.
   • CPU with a higher clock speed will mean that Programs will load faster because more fetch-decode-execute cycles will be completed.

2. Ram

   • The purpose of the RAM is to store all of the programs and data the computer system is currently using.
   • Having more RAM in your computer system will mean that More programs and data can be opened and used at the same time on the computer system.
   • RAM is volatile, meaning that the data is not stored when the computer system is switched off.

3. Hard Drive

   • The purpose of the secondary storage is to store all of the files needed for the computer system to run. For example, the operating system, programs (apps) and files
   • Having a hard drive with a higher capacity will mean that More files and programs can be saved on the computer system.
   • The hard drive is non-volatile, meaning that the data is stored even when the computer system is switched off.

4. Cores

   • The number of independent processors in the CPU which run the fetch decode execute cycle simultaneously.
     • Simultaneously: At the same time.
   • Dual core: 2 independent processors in the CPU working simultaneously.
   • Quad core: 4 independent processors in the CPU working simultaneously.

5. Clock Speed

   • The number of fetch decode execute cycles a CPU can perform per second. This is measured in hertz (Hz).
   • 1Hz – 1 cycle per second
   • 1KHz – 1000 (thousand) cycles per second
   • 1MHz – 1,000,000 (million) cycles per second
     • 1GHz – 1,000,000,000 (billion) cycles per second

6. Computer Hardware

   • Solid State
     • Advantages
       • Fastest Read and write speed
     • Disadvateges
       • Lowest capacity
     • A high performance computer or laptop.
       • A high performance computer or laptop.
     • A high performance computer or laptop.
       • Durable: Less likely to break if dropped.
   • Magnetic
     • Advanteges
       • Highest Capacity
       • Cost Effective
     • Disadvantages
       • Slowest Reand and write speed
     • A games console such as a PS4.
       • Capacity: Lots of storage needed for installing games.
     • A budget laptop.
       • Cost effective compared to solid state.
     • A school server
       • Capacity: Lots of files need to be stored.
   • Optical
     • Disadvantage
       • Not Durable
     • Advantage
       • Portable
       • Cost Effective
     • A video of a school show to share with parents.
       • Easy to carry.
     • A computer game bought in a shop.
       • Cost effective and portable (can be played on lots of devices)

7. Computer networks and security.

   • Bluetooth
     • Disadvantages
       • Cost effective
       • 10m range
       • Shortest range
     • Advantages
       • Connects two devices together!
       • Is limited to 7 devices connecting at one time
       • Can transfer music or data to other devices
       • Automatic
     • Examples
       • I left my speaker outside and i took my phone to go into the kitchen,the connection started to crackle!
       • If you walk to far away from the bluetooth connection, it won't be able to transfer data!
   • GPRS (General packet radio service)
     • disadvantage
       • Slowest data transfer speed
       • Expensive
     • Advantage
       • Gives you internet
       • Portable
       • Longest range
     • Example
       • On the way home i was using my data and when i got to school the next day my data was gone!
       • If you use all your data you will need to buy more to get data!
   • Wifi
     • Disadvantages
       • A password can also be bad as you won't be able to connect to the wifi if someone has given you permission!
       • It is not reliable; It can easily drop out because other people are using it!
       • Can't use it if it's too far from the router! You need a password!
     • advantages
       • Limited to 255 devices
       • Allows devices to connect to the Internet or communicate
       • A password is good so no one could steal your wifi
     • Examples
       • I was at home watching videos and the wifi lost connection making my videos not load!
       • Wifi can easily disconnected as other people are using it as well