Basically, they add an extra charge to all or almost all vehicles in certain zones where traffic and pollution are deemed a big problem. (treehugger.com)
What the often - unpopular - policy does is charge cars for entering certain zones of a city at certain times. (lifeedited.com)
This is especially important in an area where the government is now allowing professional fishermen to kill sharks larger than three meters that enter certain zones used by surfers and beach goers. (treehugger.com)