# Java Key Concepts

## About

Subpages consolidates the questions on foundational and intermediate Java topics such as:

* Object-Oriented Programming principles (Inheritance, Encapsulation, Polymorphism, Abstraction).
* Core APIs: Collections, Streams, Exceptions, Concurrency utilities.
* JVM internals, garbage collection, memory management.
* Java 8+ features: Lambdas, Functional Interfaces, Optionals, and Stream pipelines.