Computer Science

Computer Science

1. High-Level Languages

   • Independent of hardware
   • Translated using a compiler (all at once) or a translator (a line at a time)
   • Easier to read and understand for humans
   • Includes iteration and selection
   • Uses Boolean operators
   • Uses arrays
   • Uses an unlimited number of alphabet and numbers
   • More EFFICIENT
   • Advantages
     • Easier to write, read, debug + maintain
     • Can be used across different machines
     • Disadvantages
       • Slower than low-level languages
       • Compiler consumes memory
   • COMPILER
     • Is a complex translation as a single instruction can result in many machine code instructions
     • The code written by the programmer is called the 'source code'
     • The machine code produced by the compiler is called the 'object code'
     • When purchasing commercial software, you're buying the object code and you don't need the compiler to run the software
     • For the developer, this means that no one can copy their source code, e.g. Microsoft
     • Source code -> compiler -> object code
   • INTERPRETER
     • Executes program directly
     • Can only process one instruction at a time, so it's really slow
     • Must have it installed to run the software
     • Can be efficient with small coding + spots out errors as it's meticulous

2. Low-Level Languages

   • Used in cars, traffic lights, washing machines and
     • aeroplane programming
   • Needs an assembler to be translated, doesn't need to be translated by the machine
   • It's code-specific
   • ASSEMBLY LANGUAGE
     • Used to directly manipulate hardware and addresses critical performance issues
   • Disadvantages
     • Requires deep understanding in technical language to debug the program
     • Is difficult to understand
     • Advantages
       • Program execution is faster
       • Occupies less memory

3. Processors

   • All cores have an ALU, CU and registers