Programming languages Study Guide

Interpreters and compilers both translate high-level programming code into machine code, but they work in distinct ways. A compiler translates the whole source code at once and produces a standalone executable file, which can then run without needing the compiler again. This allows compiled programs to execute quickly since the translation is already complete. In contrast, an interpreter translates and executes code one instruction at a time at runtime; it does not create an independent executable, and the interpreter must be available each time the program runs. Errors in compiled programs are detected across the whole code before execution, while an interpreter reports errors during execution when it encounters them. Interpreted programs generally run more slowly, but interpreters offer flexibility for rapid code testing and debugging.

Programming languages are categorised into low-level and high-level based on their abstraction from machine code. Low-level languages, such as assembly language, are very close to the computer's hardware, offering direct control over CPU operations and memory. They are hardware-dependent and generally difficult for humans to write and read, requiring a deep understanding of the computer's architecture. Their primary purpose is to maximise performance and efficiently utilise limited resources in specific hardware contexts, often in operating systems or embedded systems. High-level languages, like Python or Java, are designed to be more human-readable and independent of specific hardware. They abstract away low-level details, making programming easier, faster, and less prone to errors. Their purpose is to facilitate rapid development, portability across different systems, and maintainability for a wide range of applications, from web development to scientific computing. A translator (compiler or interpreter) is needed to convert high-level code into machine-executable instructions.