Upon clicking START you will be shown 4 circles, one at a time, with increasing radii: 500, 1000, 2500, and 5000 km. The object is to move the circle to the location such that it covers the most amount of people, based on World population density data. You are scored based on how many people you cover compared to the maximum possible (score is based on the ratio of people in your circle compared to max possible – score is not an exact ratio but falls faster than that).