First Edition
Almost cards represent passengers. There are 5 kinds of Passengers like kids, highschool girls, salary men, seniors and ET(the Extra-Terrestrials).
Each card has a rank from 1 to 81 (expressed years old).

Each player has 3 kinds of buses. Each bus has limit of passengers: 3, 4 or 5. Same kind of passengers must ride same bus. But ET can change the rule.

Each round, several passengers will appear at the field.
Then, each player select a card from hand simultaneously.
According to the rank you played, you can get passenger(s) from the field and/or played.

After that, you must line passengers got to your Busstop or make ride some of your buses.

When filled, the bus will go and you get VP from passenger rode.

The game will finish when all cards are played.

Second Edition
They changed cards into tiles.
Numbers on the tiles also changed.