text: The first one to answer had a point, no one really knows if the universe is infinite. But, assuming it is, some one else said that stars dont comprise the most matter in the universe. Only stars make up only 3 percent of the total matter in the universe, dark matter and dark energy comprise about 90 percent of the matter. And remember that stars usually form in clusters (nebulae) to form galaxies. But yeah, no one really knows if the universe is inifinite or not, I mean Voyager 1 and 2 have only just left the gravitational reach of our sun, so we still have a long way to go.