Dialect of programming language C++

C++03 is a version of C++ standard published in 2003 as ISO/IEC 14882:2003. It doesn’t introduce any major changes to the language. Instead it focuses on details of language implementation which needed to be clarified to improve compilers compatibility. From programmers’ point of view the language didn’t change, and some authors, including Bjarne Stroustrup, argue that C++03 shouldn’t be treated as a separate standard but rather a bugfix for C++98.