You get a hundred in the treasury and a city with nobody in it. Zoning is the only thing you can do at first: residential brings people, commercial and industrial bring money, and each zone you lay down raises the price of the next one. A date ticks over in the corner and daily income lands whether you are watching or not.
Income buys the things a city needs next, a road, a school, billboards, a power plant, and it buys tax rises on each of the three zones, which is where the game actually lives. Push the rates and the treasury fills faster while people stop moving in. The city paper costs a coin and reports back on what you did. It is small and it finishes in an evening, which is the right length for the joke it is telling.