Object-Oriented Programming

Object-Oriented Programming (OOP) is a paradigm, designed to allow programmers to define not only the data type of a data structure, but also the types of operations (functions) that can be applied to the data structure. In this way, the data structure becomes an object that includes both data and functions. In addition, programmers can create relationships between one object and another. One of the principal advantages of object-oriented programming techniques over procedural programming techniques is that they enable programmers to create modules that do not need to be changed when a new type of object is added. A programmer can simply create a new object that inherits many of its features from existing objects. This makes object-oriented programs easier to modify.

Where It Fits

If you plan to do any advanced programming, you will need to understand and use OOP concepts.

Example of Use

OOP languages use concepts such as inheritance, polymorphism, and encapsulation to work with classes and functions. A simple example in Java shows construction of a class named CakeApplet with a method named paint():

import java.applet.*; 
import java.awt.*; 

public class CakeApplet extends Applet { 
    public void paint(Graphics g) { 
        g.drawString("I am a Cake.",25, 25); 


Object-oriented programming developed as the dominant programming methodology in the 1990s when programming languages supporting OOP techniques became widely available. Object-oriented features have been added to many existing languages, and a number of languages have emerged that are primarily object-oriented yet compatible with procedural methodology, such as Python and Ruby (coming soon to OST).

Object-Oriented Programming at the O’Reilly School of Technology

At OST, we offer courses in several object-oriented languages. To get started, explore the introductory courses linked below.  Also see the Java Programming and C# .NET Programming courses and Certificate Programs. If you have any questions or would like additional guidance, don’t hesitate to contact us—we’re here to help!

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