Strings are immutable. But String s=\"Hello\"; String s1=s+\"World\" returns HelloWorld how ?

Strings are immutable. But String s=\"Hello\"; String s1=s+\"World\" returns HelloWorld how ? ,Java, C ,C++, ASP, ASP.net C# ,Struts ,Questions & Answer, Struts2, Ajax, Hibernate, Swing ,JSP , Servlet, J2EE ,Core Java ,Stping, VC++, HTML, DHTML, JAVASCRIPT, VB ,CSS, interview ,questions, and answers, for,experienced, and fresher

  String s=\"Hello\"; 
  String s1=s+\"World\";
In the second line above, We are trying to concatenating the \"Hello\" and a new strign object \"World\". Here a new object is created \"HelloWorld\" and returned to the reference s1. Since string objects are immutable, the reference s is still pointing to \"Hello\".

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