Data abstraction:
 
            Abstraction refers to the act of representing essential features without including the background details or explanations. Classes use the concept of abstraction and are defined as a list of abstract attributes such as size, weight and cost and functions to operate on these attribute. They encapsulate all the essential properties of the object that to be created.

• The separation of the logical properties of data from the details of how the data are represented.
• The most effective weapon that computing scientists have in their fight against complexity is abstraction.
• Concentrating on the essentials and ignoring the details.
• Sometimes abstraction is described as "remembering the 'what' and ignoring the 'how'".

            Example
                    
                     Class A
                     {
                                 int a;
                     public:
                                 void display ();
                     };