I'm a secondary school student currently taking the OCR Computer Science GCSE (J276). I taught myself to program and was recently surprised by the context of a question in one of OCR's specimen papers (this one) as it goes against my knowledge of programming.
In question 5b, a question goes on to ask for a description of the differences between compilers and interpreters:
Harry can use either a compiler or an interpreter to translate the code [that he has created].
This confused me, as it seemed to suggest that the code written could either be interpreted or compiled in order to run, which would be odd as it was my understanding that languages fit into one of two boxes, interpreted (python, javascript) or compiled (c++, java), rather than fitting into both.
Is it true that a single programming language can be either compiled or interpreted based on the programmer's desire, or is this another case of OCR simplifying the course to make it easier to understand?
C is a language that is usually compiled, but interpreted implementations exist.
According to @delnan in this answer,
First off, interpreted/compiled is not a property of the language but a property of the implementation. For most languages, most if not all implementations fall in one category, so one might save a few words saying the language is interpreted/compiled too, but it's still an important distinction, both because it aids understanding and because there are quite a few languages with usable implementations of both kinds (mostly in the realm of functional languages, see Haskell and ML). In addition, there are C interpreters and projects that attempt to compile a subset of Python to C or C++ code (and subsequently to machine code).
In reality, it looks like the designers of your course said something that was true in theory, but in practice tends to be more restricted. This is found all over programming and, in fact, the world in general. Could you write a JavaScript compiler for Commodore 64? Sure, the C64 implements a full, general purpose computer system, and JavaScript is Turing Complete. Just because something is possible doesn't mean that a lot of people actually do it, though, or that it is easy.