We will discuss how Objective C runtime system works and how we can find information about the objects at the runtime. The language always behave differently compile time and runtime.
Difference among both the versions is that with the modern runtime if you change the layout of a class than you do not have to recompile the classes that inherit from it.
Objective C Runtimes
Objective C have two versions of the runtime "modern" and "legacy". The modern version comes with version 2.0 of the language.Difference among both the versions is that with the modern runtime if you change the layout of a class than you do not have to recompile the classes that inherit from it.
