Gap Year Certificate or Study Break Certificiate as you refer to it, is submitted to the University or College in case there is a break in studies. A student may take a break after class XII to prepare for an entrance exam or take admission in a course they are not interested in. After studying for a year in an institute, if they choose to apply to another institute, they can submit the Migration Certificate from the institute where they were enrolled. In other cases where a year or more have elapsed, since the student qualified +2, they have to submit a Gap Year Certificate.
Most institutes have a standard format that applicant's need to fill and attest or else they might have to submit a declaration on a Rs.100 Stamp Paper, which will also have to be notarized, giving the reason for the applicant's gap year.
It is basically a declaration stating when you qualified HSC, and that you did not take admission in any institute during the intervening period. And that the information provided by you is true.
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