using System;using System.Collections.Generic;using System.Linq;

// The difference between List and IEnumerable is

//List uses Data or RAM

//IEnum just saves the function call 

public class Program

{

    public static void Main()

    {

        func_list();

        func_Enumerable(); 

    }

    public static void func_list()

    {

        var names = new List<string> {"sam", "alexia", "simon", "sumanth", "tony", "sam", "amr", "mark", "drew"};

        List<string> moreThanFiveLetters = names.Where(w => w.Length > 5).ToList();

        //BECOMES A LIST from Function names.Where();

        //List saves it in MEMORY.

        names[0] = "benjamin";

​

        foreach (var name in moreThanFiveLetters)//Just get Data from the list

        {

            Console.WriteLine(name);

        }

        Console.WriteLine("done List \n");

    }

    public static void func_Enumerable()

    {

        var names = new List<string> {"sam", "alexia", "simon", "sumanth", "tony", "sam", "amr", "mark", "drew"};

        IEnumerable<string> moreThanFiveLetters = names.Where(w => w.Length > 5);

        //IEnumerable just saves it as a function.

        //Whenever we call foreach, only will it execute the function.

        names[0] = "benjamin";

​

        foreach (var name in moreThanFiveLetters) //Only Now it will execute ["names.Where(w => w.Length > 5)"]

        {

            Console.WriteLine(name);

        }

        Console.WriteLine("done Enumerable \n");

    }

​

}