What do you understand by ‘BLUE PRINT’ in Unreal Engine 4?

A main game logical object is called a blueprint. It is like a preface in a novel. It is an index with components of ideas together with a script on it. This is used for the purpose of editing where the Blueprint Editor is used. Behavior logic of blueprint is written using С++ class, the graph editor or the both.

Every blueprint has a parent class. This class is the class in C++. One can create their own C++ classes derivatives from the defaults options like the Actor.h and then use a custom class in blueprint as the parent class. So, this is the working process of a blueprint in Unreal Engine.