Object-oriented programming helps programmers manage complexity by modeling essential aspects of the real-world problem.
A class defines a new type in your program and is typically used as a representation for a type of thing in the problem domain.
An object is an instance of a class.
State is the current condition of an object.
Many classes define member fields, which are typically private variables visible to every method of the class.
The behavior of the class is defined with methods, which contain code to perform an action. Methods can manipulate the state of the object and interact with other objects.
The three pillars of object-oriented programming are encapsulation, specialization, and polymorphism.
Encapsulation requires that each class should be discrete and self-contained. Each class should "know" and/or "do" one discreet thing or set of things. Specialization is implemented by deriving more specific classes from generalized (base) classes through inheritance.
Polymorphism allows you to treat a collection of objects of types all derived from a common base as if they were each instances of that base type.
Analysis is the process of detailing the problem you're trying to solve.
Design is the planning of the solution to the problem.
