Object-oriented programming (OOP) is a programming paradigm that revolves around the concept of objects. In OOP, objects are instances of classes, which serve as blueprints for creating these objects. This paradigm introduced the idea of data encapsulation, inheritance, and polymorphism, which are essential concepts in modern programming languages. With OOP, developers can organize and structure their code more efficiently, making it easier to maintain and extend in the long run. By understanding the core principles of OOP, programmers can build scalable and maintainable applications, paving the way for the software development industry as we know it today.