What is a "translation unit" in C++?

c++, c++-faq

Solution

From here: (wayback machine link)

According to standard C++ (wayback machine link) : A translation unit is the basic unit of compilation in C++. It consists of the contents of a single source file, plus the contents of any header files directly or indirectly included by it, minus those lines that were ignored using conditional preprocessing statements.

A single translation unit can be compiled into an object file, library, or executable program.

The notion of a translation unit is most often mentioned in the contexts of the One Definition Rule, and templates.

Problem

I am reading at the time the "Effective C++" written by Scott Meyers and came across the term "translation unit". Could somebody please give me an explanation of the following: What exactly is it? When should I consider using it while programming with C++? Is it C++ only, or can it be used with other programming languages? I might already use it without knowing the term...

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