When we compare two objects with same content,there is a difference between “Equals and == “.
Equals :
The Equals method does the content based comparison between two objects.
== :
“==” compares only object references.
Scenarios :
Sample s = new Sample () { a = "Hey" };
Sample s1 = s;
Sample s4 = new Sample () { a = "Hey" };
Console.WriteLine(s1==s);  // True --Compares the instances 
Console.WriteLine(s==s4); // False ---Eventhough content is same,still == looks only for reference.
Console.WriteLine(s.Equals(s4)); // True --- Compares the value in field "a"  in both object and returns true.
String is an exceptional case and its immutable. It behaves with == as Equals.
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