string -the object created as a String is stored in the Constant String Pool . string biulder - that is it stores the object in heap and it can also be modified .

Please refer to the following URL to know the differences between String and StringBuilder,http://onlydifferencefaqs.blogspot.in/2012/08/oops-difference-faqs-4.html

Hi Sathish,
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Hi Sathish,