What is a “translation unit” in C++

Question

I am reading at the time the \"Effective C++\" written by Meyers and came across the term \"translation unit\".

Could somebody please give me an explanation of:

Answer 1

A hard question to answer definitively. The C++ standard states:

The text of the program is kept in units called source files in this International Standard. A source file together with all the headers (17.4.1.2) and source files included (16.2) via the preprocessing directive #include, less any source lines skipped by any of the conditional inclusion (16.1) preprocessing directives, is called a translation unit. [Note: a C++ program need not all be translated at the same time. ]

So for most intents and purposes a translation unit is a single C++ source file and the header or other files it includes via the preprocessor #include mechanism.

Regarding your other questions:

2) When should I consider using it when programming with C++

You can't not consider it - translation units are the basis of a C++ program.

3) If it is related only to C++, or it can be used with other programming languages

Other languages have similar concepts, but their semantics will be subtly different. Most other languages don't use a preprocessor, for example.