Think C v. 4.0 offers near ANSI C compatibility, a few crucial C++ features which allow object-oriented programming, and a few features not available in C++. C++ on the other hand is generally ANSI C compatible and adds several object-oriented features not available in TC.
This appendix details the differences among ANSI C, Think C v. 4.0, and C++. Conditional compilation* may be used to obtain portability from TC to C++.