The Sun is an average-sized star. The biggest stars are more than 100 times as massive as the Sun, and the smallest stars are less than 1/10th as massive as the Sun.

As far as comparing to other star *systems*--More than half of all stars are in binary or other multiple star systems, in which two or more stars orbit around each other in a single "system". There have also now been planets discovered around other stars besides the Sun, although very few of those systems look like they could be much like our solar system in terms of the orbits of the giant planets. But this may just be because solar systems like ours are hard to find. You can find out more about planets around other stars