What is Collection Inialization ?

Yes, when creating Collection. At Collection Level the intialization of object is done otherwise we can say inside Collection according to object values also we can perpare the list  of objects or collection.
Ex:

 class College
    {
        public string CollageName { get; set; }
        public string CollegeLocatoion { get; set; }  
    }
then Create a Collection

static void Main()
        {
            List<College> cobj = new List<College>
            {
                new College{CollageName="PES Collage", CollegeLocatoion="Kakinada"},
                new College{CollageName="Nehru Collage", CollegeLocatoion="Annavaram"},
                new College{CollageName="ABCD Collage"}              
            };
            Console.WriteLine(cobj[0].CollageName);
            Console.WriteLine(cobj[0].CollegeLocatoion);
            Console.WriteLine(cobj[1].CollageName);
            Console.WriteLine(cobj[1].CollegeLocatoion);
            Console.WriteLine(cobj[2].CollageName);
            Console.WriteLine(cobj[2].CollegeLocatoion); // null
            Console.ReadKey();
        }
here Collection count is 3 means 3 college objects and thrid object CollectionLocation is null.
so convent way of initialization of objects.