OBJECT ORIENTED PROGRAMMING IN A NUT SHELL... ALMOST

So you want to learn object oriented programming?!

Good choice .But before you start learning with the style of an enraged spanish bull  you should understand its premises.

Object oriented programming (OOP) is a programming paradigm,that means a style of coding(google for paradigm).
Its purpose is to solve problems faced by coders and to make efficient the time spent coding.

Let's understand a computer programming language. Computer programming languages are cataloged in to 4 generations. The first generation is the machine code,pure CPU instructions.The 2nd generation are the assembly languages . The third generation are languages like C/C++,C#,Java,Delphi.
The 4th generation doesn't matter right now.

The generations appeared because when you do complex stuff using tiny,finite and simple bricks(machine instructions) you observe  patterns. And if you give those code patterns a simple human readable name, you can make another program ( a compiler) to replace that name with the code it represents.

At one point people figured this:

With computer programs you are trying to solve problems from the real world. By programming you are actually describing  OBJECTS from the real world in the solution world(the computer). You are making a functional/mathematical description of OBJECTS from the real world.
OBJECTS of one kind (species) have a mold(CLASS).

Now coming back to 3rd generation languages. In those languages you toy around with variables and functions. What if you can give a common name to a number of functions and variables that describe an OBJECT(rallied under one name,symbol)? To make an object out of different variables and functions we need to ENCAPSULATE those functions(methods) and variables(attributes). What if we want to INHERIT from another mold(CLASS) functions and variables or add functions and variables to an existing mold(CLASS) and give it a new name: we need to INHERIT.

The basics concepts of OOP:
 -ENCAPSULATION
-INHERITANCE
-POLYMORPHISM (one name,different implementations|concept applied to functions a.k.a methods)
GOOGLE FOR MORE.