Object-Oriented programming refers to the concept in high-level languages, such as Java and Python that uses Objects and classes in their implementations. OOP has four major building blocks which are, Polymorphism, Encapsulation, Abstraction, and Inheritance. There are other programming paradigms, such as Procedural programming in which code is written sequentially.
Python and Java are multi-paradigm high-level, programming languages. This means they support both OOP and procedural programming. A programmer decides on the paradigm to use based on their expertise and the problems they're trying to solve. However, there is no debate that OOP makes programming easier, faster, more dynamic, and secure. This is a major reason Java and Python are two fo the top most popular programming languages in the world today