Six Stars in Total
The flag of Australia features six white stars set against a blue background. They fall into two groups. There is one large star, known as the Commonwealth Star, and there is a group of five stars that together represent a constellation called the Southern Cross.
The Commonwealth Star
The single large star, positioned below the Union Jack, is the Commonwealth Star, sometimes called the Federation Star. It has seven points. Six of those points stand for the six states that joined together to form Australia, and the seventh point represents the countrys territories. This star is a symbol of the union of Australia into one nation.
The Southern Cross
The other five stars form the Southern Cross, a constellation that can be seen in the night sky of the Southern Hemisphere. Four of these stars are larger with seven points each, and one is smaller with five points. The Southern Cross has guided navigators for centuries and points to Australias location in the southern half of the world. A common mix-up is to confuse the number of stars with the number of points on the Commonwealth Star - but the flag itself carries six stars in all.
Source
This article was written using information from Wikipedia.