Online Computer Dictionary

(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.