What is the difference between object-oriented and procedural programming?

Answer 1

Procedural programming can sometimes be used as a synonym for imperative programming. To a programming paradigm based upon the concept of the procedure call. Procedures, also known as routines, subroutines, methods, or functions (not to be confused with mathematical functions, but similar to those used in functional programming) simply contain a series of computational steps to be carried out. Any given procedure might be called at any point during a program's execution, including by other procedures or itself. The important features of Procedural Programming. 1. Programs are organized in the form of subroutines and all data items are global. 2. Program controls are through jump(goto) and calls to subroutines 3. Subroutines are abstracted to avoid repetitions. 4. Suitable for medium sized software application 5. Difficult to maintain and enhance the program code. K E Narayana

Answer 2

Procedural programming can be thought of as a series of actions or procedures that can be performed upon a given set of data. Even with OOP we still use procedural programming methods, but OOP allows us to extend the way in which the data is physically stored, manipulated and, more importantly, validated.

With procedural programming alone, data would be passed from one function to another in order to manipulate it. Passing data around like this is cumbersome at best, but the data itself is fully exposed to rogue manipulation which could invalidate the data at any time. Structured programming improves things by allowing the procedures themselves to be organised in a more systematic fashion, but the data itself is still subject to undue exposure.

OOP basically combines a set of data with the procedures (or methods) that can physically act upon that data. In essence an object is a data structure with built-in methods, but we can limit the amount of exposure we give the data by creating a controlled interface to that data. In general, the interface will include mutators to set the data, operations to manipulate the data and accessors to retrieve the data. The data itself can be safely hidden from view and the object's methods ensure the data is modified in a controlled manner, thus ensuring its integrity. The flexibility of an object is such that we can expose as much or as little of the data and its interface as we desire.

As with structures, objects can be combined to create highly-complex data structures. But unlike structures, each object takes care of its own data. Such structures would be difficult if not impossible to implement with procedural programming alone.

Answer 3

Object-oriented programming has most, or all, of the features found in procedural programming. Apart from that, in object-oriented programming you create classes, and you create objects based on the classes. Classes (and their objects) have fields (variables defined at the class level) and methods (functions defined at the class level). Some of the features found in most object-oriented languages are encapsulation (which allows hiding the internal implementation of a class), inheritance (which allows one class to reuse the definition of another class, and add additional features), and polymorphism (which allows different classes to have methods with the same name). All these features are NOT used in pure procedural programming.