Why are low-level languages still useful?

Because they give more direct control over hardware and can be very efficient for specific tasks.

What is the main difference between a compiler and an interpreter?

A compiler translates the whole program first, while an interpreter works through it one line at a time.

2.5.1

Languages

Q: Do I need to know assemblers for OCR J277?

No. Detailed knowledge of assemblers is not required.

Programming languages exist at different levels. You need to compare high-level and low-level languages, understand why translators are needed, and explain the differences between compilers and interpreters. The key is understanding the trade-offs rather than memorising unnecessary technical detail.

20 exam questions 8 flashcards

What you need to know

Explain the differences between high-level and low-level languages.
Explain why translators are needed.
Compare compilers and interpreters, including benefits and drawbacks.

Big Picture

High-level and low-level languages

Different languages are useful for different reasons.

Type	Strength	Drawback
High-level	Easier for humans to read, write, and maintain	Less direct control over hardware
Low-level	Closer to machine code and hardware	Harder for humans to read and write

Machine Code

Why translators are needed

The processor cannot run high-level code directly.

Source code must be translated into machine code so the processor can execute it. That is why translators are needed.

Comparison

Compiler vs interpreter

You may be asked to compare these directly.

Translator	How it works	Benefit	Drawback
Compiler	Translates the whole program before running	Executable can run again without retranslation	Errors may be reported after the whole translation stage
Interpreter	Translates and runs one line at a time	Good for testing and debugging line by line	Program usually runs more slowly

Not required

Detailed knowledge of assemblers is not required.

Key takeaways

High-level languages are easier for humans to read and write.
Low-level languages are closer to machine code and can give more direct hardware control.
A translator is needed because the CPU only runs machine code.
A compiler translates the whole program, while an interpreter translates and runs code line by line.

Glossary

High-level language: A language designed to be easier for humans to read and write.
Low-level language: A language much closer to machine code and hardware.
Translator: Software that converts source code into machine code.
Compiler: A translator that converts the whole program before it runs.
Interpreter: A translator that converts and runs code line by line.

Test yourself

Common questions