Curriculum Portal

neurologyYou need to know

• High-level programming languages use human-readable statements and abstractions that make programs easier to write, understand and maintain.
• High-level languages are largely independent of a computer’s processor architecture, so the same source code can often be translated for different systems.
• Low-level programming languages use instructions that are closely related to the processor’s instruction set and hardware architecture.
• Low-level languages give programmers direct control over hardware and memory, which can support efficient use of processing time and storage.
• Low-level programs are generally more difficult for humans to read, write, debug and maintain than equivalent high-level programs.
• Programs written in a low-level language are usually processor-specific, so they are less portable between systems with different processor architectures.
• A translator converts source code written by a programmer into machine code that the processor can execute.
• A translator is needed because a processor directly executes machine-code instructions rather than high-level source code.
• A compiler translates an entire source program into machine code before the resulting program is executed.
• A compiler reports detected errors during compilation and does not usually produce an executable program until blocking errors have been corrected.
• Once compiled, an executable can be run repeatedly without translating the source code again, so execution is usually faster than with an interpreter.
• Compiled programs can be distributed without sharing the original source code, although separate versions may be needed for different operating systems or processor architectures.
• An interpreter translates and executes source code one statement at a time while the program is running.
• An interpreter normally stops when it reaches an error, which makes it easier to locate and test individual faulty statements.
• Interpreted programs require the source code and a suitable interpreter each time they run, so they are generally slower than compiled programs.
• An Integrated Development Environment (IDE) combines tools for writing, translating, testing and debugging programs in one application.
• An IDE editor can provide features such as syntax highlighting, automatic indentation, line numbering and code completion to make source code easier to create and inspect.
• Error diagnostics identify problems in source code and provide messages that help the programmer locate and correct syntax or run-time errors.
• An IDE’s run-time environment allows a programmer to execute and test a program without leaving the IDE.
• An IDE includes or connects to a compiler or interpreter so that source code can be translated and executed during development.

• Compare high-level and low-level languages in terms of readability, hardware control, portability, development time and processor dependence.
• Select a high-level or low-level language for a stated task and justify the choice using the task’s requirements.
• Explain why a given source program requires a translator before a processor can execute it.
• Compare compilers and interpreters by describing when translation occurs, how errors are reported, execution speed and software distribution.
• Choose between a compiler and an interpreter for a stated development scenario and justify the choice using relevant benefits and drawbacks.
• Use an IDE editor’s syntax highlighting, indentation, line numbering and code completion features to enter and organise source code accurately.
• Use error diagnostics to locate, interpret and correct syntax and run-time errors in a program.
• Use an IDE’s translator and run-time environment to translate, execute, test and refine a program.