GCSE Computer Science.

GCSE Computer Science.

1. Computer Systems

   • CPU
     • Central Processing Unit
       • In theory the brain of the computer, it is in charge of processing instructions and performing tasks.
     • Fetch, Decode, Execute cycle
       • When the computer is switched on, the fetch, Decode, execute cycle begins an endless process of FETCHing data, DECODingng the data and EXECUTES the insturctions.
     • Computer Hardware
       • Computer hardware is the components that a computer system is made up of.
       • Case, Power Supply, Motherboard, Expansion cards, Storage devices and input/output peripherals.
     • Arithmetic and logic unit (ALU)
       • Arithmetic Logic Unit (ALU)
         • The ALU solves mathematical problems, to help the CPU
   • RAM and ROM
     • Random access memory (RAM)
       • Read only memory (ROM)
         • Read at a high speed
         • Can't be edited by program instructions
       • Accessed randomly
       • Most common type of memory
   • Importance in reliabilty
     • We have grown very dependant on computer systems so there is a need for reliabilty.
       • Cars and planes require a computer system to work
         • Without them life would be very difficult.

2. Python

   • # = note to self, ignored by python
   • print("Hello World") will print Hello World
   • Python is a coding software.

3. Binary

   • 1=on
   • 0=off
   • A computer doesn't understand english language , only 0s and 1s