Abstraction is a fundamental concept in computer science and programming, particularly within object-oriented programming (OOP). It involves simplifying complex systems by hiding unnecessary details and exposing only the essential features to the user. This allows developers to focus on high-level functionalities without getting bogged down by intricate implementation specifics. Abstraction can be achieved through abstract classes and interfaces, which define a blueprint for other classes while concealing the underlying logic. By employing abstraction, programmers can enhance code reusability, maintainability, and security, making it easier to manage and evolve software systems over time.