It is important to distinguish between these. The interpretation of the internal representation. The operations that can be performed on the item. A data item is defined using a data declaration. A data declaration introduces a data item.
Assignment is the process of associating a value with a data item.
Alternatively, on the right hand side of the assignment operator we could have used an identifier, an expression or the result of a method call. In Java this cannot be done where data items are used as formal parameters to methods. In Table 1 a short Java class definition is presented to illustrate the different forms of data initialisation available in Java. Note that in keeping with the spirit of OOP all the data fields are declared to be private, i.e. they can only be accessed from within the class where they are declared. The content of the methods describes the algorithmic part of the program.