The Gallaghers are a poor family living on the Southside of Chicago trying to make ends meet. William H Macy is the patriarch, and Emmy Rossum is the oldest daughter(about 21 or 22), who actually runs the household. Macy's wife is gone, and Macy himself is a jobless alcoholic, though at one point we learn he is also a schizophrenic. Through all the madness of living on the bottom rung of society, the family sticks together with fierce loyalty and faithfulness.
If you enjoyed "Weeds" or "Californication", then this series is for you. I would expect many more seasons, as there are a lot of places the writers and actors could take this show.