Object Oriented Programming Concepts And Principles Explained

Object Oriented Programming
Object Oriented Programming

Software developers and engineers deploy object oriented programming in a wide variety of projects. This approach to programming went from the academic world of the 1960s to the computer boom of the 1980s because of its modularity. Programming languages like Java and Python facilitate object oriented programming for personal and commercial projects.

Newcomers to the software industry need advanced knowledge of this programming style for long-term success. Understanding object oriented programming concepts and advantages starts with a history lesson. We can answer the question, “What is object oriented programming?” after we find out why it was created.

Origins of Object Oriented Programming

Computer scientist Alan Kay is often cited as the creator of this programming style. Kay was a student at the University of Utah when he sought an alternative to the functional programming norms of the day. In his mind, existing programming schemes were heavily reliant on data and too intricate for increasingly complex systems.

Object oriented programming combines data and functions into classes that inform objects. Kay explained the concept of objects and classes by saying:

“My math background made me realize that each object could have several algebras associated with it, and there could be families of these, and that these would be very very useful.”

Kay’s development of object orientation focused as much on communication between objects as the objects themselves. Objects pass messages to activate processes for functions rather than directly communicating the function name. PanonIT summarizes this concept of message sending as the “sending object will just send a message to one object and the other object will decide what to do.”

Expanding the Reach of Object Oriented Programming

This research was informed by the Advanced Research Projects Agency Network (ARPANET) designed by the U.S. Department of Defense in 1969. Kay saw the need for a programming language that was less centralized and more portable based on ARPANET’s model. The predecessor to today’s Internet, ARPANET was integral to solidifying object oriented programming in computer science.

Kay joined the Xerox Palo Alto Research Center (PARC) and worked on an object oriented system called Smalltalk-80. The August 1981 issue of Byte Magazine on the system is widely credited as introducing object oriented programming to the public. Fellow PARC designer Adele Goldberg wrote:

“A goal in the design of the Smalltalk system was to create the Taj Mahal so that programmers can modify it by building application kits, which are specialized extensions and/or subsets of the system whose parts can be used by a nonprogrammer to build a customized version of the system.”

Core Principles of Object Oriented Programming

Object oriented programming remains frequently used by programmers because it embodies portability and functionality. Computer scientists have identified four core principles that fit into these themes: 


Encapsulation means that similar functions and data are bound together into classes that are mobilized to define objects. Kay wanted to keep data in the background of programming so that simple errors wouldn’t wreck software. This principle means that objects are protected from bugs when systems are scaled up or changed.


Programming work can be repetitive with similar code used across different functions. Object oriented programming allows for the creation of subclasses that share code with the parent class. Inherited code saves time and reduces errors across components with similar characteristics.


Abstraction in programming can be explained by thinking about the device used to read this post. A mobile phone, laptop, or desktop presents a user-facing display without the complex coding that makes it work. Programmers use objects and classes to focus on what is essential in most of their work.


Alan Kay saw the potential for genericity among objects whereby multiple objects could be combined into new forms. This concept stems from the other three principles because objects are confined, replicable, and light on complexity. Genericity became known as polymorphism over time to capture the many permutations of objects.

At the root of polymorphism is a word that easily describes the process— metamorphosis, meaning to transform. Dr. Peter M. Maurer, faculty member in Baylor University’s School of Engineering and Computer Science, takes a closer look at metamorphic programming as an effective tool for creating efficient and elegant solutions to many programming problems in his recently published paper, 'Metamorphosis, State Machines, and Object Oriented Design”.

The Advantages of Object Oriented Programming

Software development projects may require functional, logical, scripting, or object oriented programming. Successful developers can identify appropriate programming types and languages for their projects. Stack Overflow’s 2020 Developer Survey found that the most popular programming languages were:

  • JavaScript (69.7% of respondents)
  • Python (41.6%)
  • Java (38.4%)
  • C# (32.3%)
  • TypeScript (28.3%)

These languages are popular in part because they can be applied to different paradigms. For example, Python and TypeScript are designed for object oriented programming but can be used for functional programming. Developers also use these languages because they maximize the advantages of this programming style.

Replicating the Real World

Software based in object oriented programming is structured in an intuitive way for many designers. People tend to cluster people, places, and things into categories as they process the world around them. Object oriented programming does something similar by grouping like components.

Replicating real-world features is important because software acts as a translator between users and technology. For example, a developer working on city transit software doesn’t need extensive code to group different vehicle types. They can create Bus, Ferry, and Train classes with objects for models in the fleet.

Programming Adaptability

Our transit software developer can reuse inherited code for fares and route scheduling. They can group objects for maintenance or on-demand services. Changing data and functions within one class cascades through all of its associated objects.

These elements lead to a low-cost method for software development. Product testing requires less time and fewer resources because the focus is on classes rather than particular strings of code. Issues found when software reaches consumers can be quickly corrected by changing classes and objects.

Learning Advanced Software Skills at Baylor University

Object oriented programming is a starting point for software and system development. Rising expectations in the software industry mean that developers need advanced programming skills. Baylor University’s Online Masters in Computer Science produces well-rounded graduates who can handle future challenges in the field.

This entirely online program is shaped through leading academic and industry insights and is led by leading experts in the computer science field. Degree candidates are taught to consider how their work impacts people around the globe. This focus on ethical and innovative thinking sets graduates apart when they enter the job market. 

Every Online Masters in Computer Science student completes six core courses for a shared foundation. These classes explore topics relevant to the field at present and in the future including:

  • Advanced Algorithms
  • Advanced Data Communications
  • Intro to Machine Learning
  • Software Engineering

Baylor University offers Data Science and Software Engineering concentrations as part of this program. Developers interested in object oriented programming add valuable skills to their resumes with the Software Engineering track. This four-course path includes the following courses:

  • Advanced Object Oriented Development
  • Advanced Software Engineering
  • Distributed Systems
  • Software Verification & Validation

Graduates of Baylor University find their prospects amplified by the school’s national reputation. U.S. News & World Report ranked Baylor #76 among Best National Universities, placing the university among the top 5% in the nation. The publication also recognized Baylor’s commitment to innovation by ranking the university #25 among Most Innovative Schools in the nation. 

To find out more about object oriented programming, its concepts and principles, and how Baylor University’s Online Computer Science degree programs can help you become a software innovator, get your free program guide or connect with one of our expert enrollment advisors, who are standing by to help answer any questions you may have.