In object-oriented programming, a class is an extensible program-code-template for creating objects, providing initial values for state (member variables) and implementations of behavior (member functions or methods).
In object-oriented programming, a class is an extensible program-code-template for creating objects, providing initial values for state (member variables) and implementations of behavior (member functions or methods).
When an object is created by a constructor of the class, the resulting object is called an instance of the class, and the member variables specific to the object are called instance variables, to contrast with the class variables shared across the class.
In some programming languages, classes are a compile time feature only (new classes cannot be declared at runtime). In other languages, classes are first-class citizens, and are generally objects (typically of type Class or similar). In these languages, a class that creates classes within itself is called a metaclass.