Notes

An object is anything that can be represented by data in a computer's memory and manipulated by a computer program. Numbers, Text, Pictures, Sound, and Video
An object can be something in the physical world or even just an abstract idea.
An Airplane, for example, is a physical object that can be manipulated by a computer.
A bank transaction is an example of an object that is not physical.
To a computer, an object is simply something that can be represented by data in the computer's memory and manipulated by computer programs.
The data that represent the object are organized into a set of properties.
The values stored in an object's properties at any one time form the state of an object.
Computer programs implement algorithms that manipulate the data.
In object-oriented programming, the programs that manipulate the properties of an object are the object's methods.
We can think of an object as a collection of properties and the methods that are used to manipulate those properties.
A class is a group of objects with the same properties and the same methods.
Each copy of an object from a particular class is called an instance of object.
The act of creating a new instance of an object is called an instantiation
A class can be thought of as a blueprint for instances of an object.
Two different instances of the same class will have the same properties, but different values stored in those properties.