Compilers, Interpreters, VMs and JIT
The distinction between a compiler and an interpreter is one that can cause controversy. One programmer's compiler is another's interpreter and the whole subject gets very murky when you throw in the idea of the Virtual Machine and Just In Time compilation. So what is it all about?
If you want to start an argument between programmers or software engineers then just say “language X is implemented by an interpreter”.
If that doesn’t cause a heated exchange, then change “interpreter” to “compiler” in the same sentence. For while there are languages that are generally accepted as being implemented usually as one or the other, the situation is rarely clear cut.
Back in the early days of computing the distinction was much more important and the debate about compilers versus interpreters would rage in the pages of any magazine or journal and verbal wars were common. Today, with more powerful machines, the issue isn’t quite as important but it can still raise a good argument!
It can also be the deeper cause of a language war. For example, C++ v C# isn't just about which language is better it is also about the way that the languages are generally implemented. C++ is usually compiled to machine code where C# is usually compiled to an intermediate code and then interpreted or JITed.
