Programming

Programming

1. High level / low level programming

   • High level has to be translated
     • Python, BASIC, Javascript
     • Has to be translated
     • Uses language that is easier to understand by humans
   • Low level is understood by the processor
     • Assembly language
       • Codes specific to a type of processor
       • INP, LDA, OUT
       • Written as each instruction would be processed
     • Machine code
       • Binary code for each instruction and register location

2. Translation

   • Assembler
     • Turns assembly language into machine code
     • Only can be used in low level programming
   • Complier
     • Creates an executable file to run the program
     • Would be used for proprietary software
     • Once it is compiled it doesn't need the original source code
   • Interpreter
     • Executes the source code directly
     • Used when creating a program
     • Would be used on open source software

3. Control flow

   • Sequencing
     • The order through an algorithm
   • Selection
     • IF THEN ELSE
   • Literation
     • Loops
       • WHILE or FOR

4. Algorithms

   • Solving problems 1 step at a time
   • Processors can only process 1 instruction at a time
     • Testing
       • Logical error
         • Human error with the construction of the algorithm
       • Run-time error
         • An error in the program es stuck in a loop
       • Syntax error
         • Not a correct command for the coding language being used

5. Pseudocode

   • Used for planning algorithms
   • Should allow a programmer to write it in any language
   • Key words written in capital letters (INPUT, IF, WHILE)

6. Data types

   • Variable or constant
     • Variable changes during the program eg score in a game
     • Constant stays the same eg Pi
   • Operations are mathematical symbols eg < > + -
   • Arrays are lists of the same data types
   • Integers and real numbers
     • Integer is a whole number
     • Real (sometimes called float) can have decimal plaxes