4a317c29_lian_Broadcasting_Corporation___Definition
[Term] Deficit/Debt [Definition] 
The deficit is just the amount of money that the government spends beyond what it receives in a financial year. Just because you return the budget to surplus doesn't mean that the debt incurred by the previous deficits disappears. Any deficits, or shortfalls, instead are added to existing government debt, which currently sits at $319 billion. While $319 billion sounds like (and is) a lot of money, by international standards Australia's public debt is quite low, sitting at 21 per cent of GDP, the second lowest of the advanced economies - and that's just gross debt, which doesn't include the value of Australia's financial assets, such as the Future Fund. However while government debt can pose problems, it isn't quite the same as personal debt and can often serve a purpose. Governments take on debt by issuing bonds to investors that are paid a return, with ratings agencies allotting a credit rating to government debt. A high credit rating, such as the one Australia has, allows governments to borrow at a very low rates, with investors trading profit for security. Some economists argue this ability to borrow at a lower rate than the market should be use to fund infrastructure projects that are likely to make a profit, as well as boosting productivity.
Budget 2014: Deficit tax may raise a lot less than Treasury forecasts says analyst - ABC News (Australian Broadcasting Corporation)
Definition