Except in prayers, it is recommended that the to salām be better than the salām itself. For example, if one says ‘salāmun ʿalaykum’, the other person should ‘salāmun ʿalaykum wa raḥmatul lāh’. Seventh: one intentionally laughs aloud. If one laughs aloud involuntarily but what led him to do so was of his own volition, or, based on obligatory precaution, even if it was not of his own volition, then, if there is enough time for him to perform the prayer again, he must do so.
However, if he laughs intentionally but without making any noise, or he inadvertently laughs aloud, his prayer is correct.