Revision

Revision

1. CPU

   • What is the purpose of the CPU?
     • Commonly known as the brains of the computer the CPU is responsible for executing sequence of stored instructions called a program
   • Clock Speeds
     • The operating speed of a computer or its microprocessor, expressed in cycles per second
       • 1 Hertz = 1 cycle
       • 1 kilohertz = 1,000 cycles
       • 1 megahertz = 1,000,000 cycles
       • 1 Gigahertz = 1,000,000,000
   • Dual core and Quad core
     • A dual core has 2 two cores meaning whatever the amount of Hertz it has it will go X2 the speed
     • A quad core has 4 cores meaning whatever the amount of of Hertz it has, it will go 4X the speed

2. Storage types

   • Magnetic storage
     • Non volitile
     • Store large amounts of data easily
     • Data can be directly read from the hard disk
     • Not very Durable
     • Gradually lose their charge over time
     • The data can not be transfered easily
   • Solid State drive
     • Faster start up as there are no moving parts
     • Far faster than other storage types
     • Longer lifetime (Up to 10 years)
     • Commomly more expensive than other storage types
     • Limited write cycles until wear out (100,000 - 300,000)
     • Slow Random write speeds
   • Optical drive
     • Non volitile
     • Good durability
     • Data can be transfered easily
     • Optical discs require special drives to read/write
     • Not as much capacity as other storage types
     • Not compatible with other drives

3. Computer Components

   • hard drive
     • It's use is to be a storage device for the computer to keep all files, programs and the OS when the computer is not in use (When it has no power) they are volatile storages
   • RAM
     • Where the OS, programs and data in current use is kept and how application are run
   • Why Improving them both increases performance
     • It increases performance not only to have a high storage capacity but also to open programs quicker and have more programs and applications open and still be able to retain a fast cycle speed

4. Programming

   • ("") All outputted text must be in speech marks
   • To output text use the term 'print'
   • To get the user to input a string use the term 'prompt'