Principles of programming

• High-level languages


  Is a programming language that allows code to be written. Some programmers prefer to use high-level programming languages, as they are easier to understand, learn and program.
• Examples of high-level languages


  • Java
  • C++
  • Python
• Machine code


  Opposite of a high-level language, in that it does not resemble any natural language and is made up entirely of bit patterns (instructions or data) that can be executed directly by the CPU.
• Example of machine code


  • Opcodes
  • Operands
• Low-level languages


  Requires knowledge of the internal structure of the CPU and is therefore very specialised. The program statements are written for a particular type of CPU and make direct reference to specific internal registers.
• Uses of high-level languages

  Used when the execution speed is not the most critical factor

  e.g. in common productivity applications

  Most modern applications such as commercial database packages, operating systems, e-commerce software and social media apps are developed using a high-level programming language.
• Uses of low-level languages


  Some programmers may wish to program directly in machine code or use assembly code. This is primarily done when programming device drivers or embedded systems, where fast execution speeds are critical.