Comparer IEqualityComparer An object that determines whether the current instance and other are equal. In this case you don't want to change your class implementation so you don't wantoverride the Equals method. this will define a general way to compare objects in your application. Other types which implement structural equality/comparability https://claytonozipv.pages10.com/temel-İlkeleri-c-istructuralequatable-nerelerde-kullanılıyor-63828781