Nestosh React Js Developer interview questions

1- Introduce yourself. Started from the very first step. OOP. They ask me to rate my OOP concept from a scale of 1 -10. Four pillars of OOP? What is inteheritance? Polymorphysm? Abstraction? Encapsulation? Type of Polymorphysm? And also define those. Interfaces? Type of inheritance. can we extend one class from two other classes I said yes and then they ask me how? Then the react JS Question come. What is React JS? Why we use React Js? what is a compoenets? what is the diff btw class and function components? what is state in a components can we define our state in a components? How? what are the stages of components? Ans: there are four stages of a component. what are the features of ES6 that are not in the ES6 specifically to the react js? How do we make react js render the server-side script?