How do you explain OO to new programmers? [closed]

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Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 8 years ago. Improve this question My relative is studying programming and has a hard time understanding classes. He has trouble understanding for example that you need to instantiate it, that methods cannot access variables in other methods and if you change a variable in one instance of a class it doesn't change for other instances. I've tried to use analogies like a class definition is like a blueprint of a house. And instances are houses made from that blueprint. How do you explain classes and OO in general? JavaScript questions and answers, JavaScript questions pdf, JavaScript question bank, JavaScript questions and answers pdf, mcq on JavaScript pdf, JavaScript questions and solutions, JavaScript mcq Test , Interview JavaScript questions, JavaScript Questions for Interview, JavaScript MCQ (Multiple Choice Questions)

Answer 1

Seriously use Animals, it works great. And that's what nailed the concept for me years ago. Just found this C# code. It seems good // Assembly: Common Classes // Namespace: CommonClasses public interface IAnimal { string Name { get; } string Talk(); } // Assembly: Animals // Namespace: Animals public class AnimalBase { private string _name; AnimalBase(string name) { _name = name; } public string Name { get { return _name; } } } // Assembly: Animals // Namespace: Animals public class Cat : AnimalBase, IAnimal { public Cat(String name) : base(name) { } public string Talk() { return "Meowww!"; } } // Assembly: Animals // Namespace: Animals public class Dog : AnimalBase, IAnimal { public Dog(string name) : base(name) { } public string Talk() { return "Arf! Arf!"; } } // Assembly: Program // Namespace: Program // References and Uses Assemblies: Common Classes, Animals public class TestAnimals { // prints the following: // // Missy: Meowww! // Mr. Bojangles: Meowww! // Lassie: Arf! Arf! // public static void Main(String[] args) { List animals = new List(); animals.Add(new Cat("Missy")); animals.Add(new Cat("Mr. Bojangles")); animals.Add(new Dog("Lassie")); foreach(IAnimal animal in animals) { Console.WriteLine(animal.Name + ": " + animal.Talk()); } } } And once he's got this nailed, you challenge him to define Bird (fly), and then Penguin (fly!?)