(RTTI) Facilities included in C++compilers to allow the type of an object to be determined at run time. This facility, found in good C++ compilers and some other high level languages, adds type infORmation to memORy resident objects (i.e. type name OR unique type-id). This allows the run-time system to determine if an object is of a specific type, fOR example, to ensure that a cast of an object is valid. (1996-04-15)