The Fission Theory: This theory proposes that the Moon was once part of the Earth and somehow separated from the Earth early in the history of the solar system.
This provides modular approach to programming. Classes. A class is a concept used in object oriented programming languages such as C++, PHP, and JAVA etc. Apart from holding data, a class is also used to hold functions. An object is an instant of a class. In case of variables, the type is the class whereas the variable is the object.
Instance methods of the class can also not be called from within a class method unless they are being called on an instance of that class. Instance methods. on the other hand require an instance of the class to exist before they can be called, so an instance of a class needs to be created by using the new keyword.