National debt is the total amount amount of money that a government has borrowed. National deficit is total of all previous annual government deficits. Keep in mind that a deficit is the difference between what a government takes in and what it spends. The two are related because when the government is unable to fully repay any debt it has accrued that money becomes a part of the annual national deficit. So as the amount of national debt increases so does the amount of national deficit.
He vetoed more bills in his term of office than all the previous presidents put together. Jackson was also the first to use the pocket veto, a delaying tactic in which the President does not sign a bill within ten days of the end of the Congressional term, preventing it from becoming law.