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.
Fields are the data for the class. Methods are the sequences of statements that operate on the data. Fields are normally specific to an object--that is, every object constructed from the class definition will have its own copy of the field. Such fields are known as instance variables.