Now u add s= s+"Technologies";
so it will NessTechnologies because you append. and assign
new varible,means that new addition is assigned to s

take one example for more clarity

String x = "Java";
x.concat(" Rules!");
          System.out.println(x);

output is x=java
because string is immutable.............think hard on it


Consider the following another example---------and think
about that

public class NewClass {

    public static void main(String as[])
    {
        String s="abc";
      String  s1=s+"cde";
        System.out.println(s);
          System.out.println(s1);


String x = "Java";
x.concat(" Rules!");
          System.out.println(x);
    }

}
output is
s=abc;
s1=abcde
x=java

since u have added cde in s but still from the output it is 
abc...............means string is immutable,

For more contact me
Anjani Kumar jha
09623154095
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