What is abstraction of objects in object oriented terminology?

Abstraction is one of the important aspect of all programming, not just object oriented programming. Abstraction serves as a way model the program objects with the real world problem. For example, if you were trying to write an address book program, you would use abstractions such as names, addresses, phone numbers, alphabetical order, and other information associated with an address book. You would also define operations for manipulating the attributes such as adding a new name or changing an address. Abstraction is thus modeling the real world in terms that can be implemented as a computer program and can be represented as a class and objects.
Designing with objects can be challenging, and it is not always easy to find the right objects for your model, but once you learn to think in objects, the process becomes almost second nature. Almost anything you need to model in software can be considered an object viz a temperature sensor in a control system, a person in a srudent in a class, a doctor in a hospital, a worker in a factory, etc. Each of these objects has attributes and responsibilities. In the context of abstraction, an object is a thing or concept. It can be a real-world thing or concept, or an abstraction of a thing or concept, expressed as a software representation.