Pachinko is a similar kind of game to pinball but played on a vertical machine, and without the flippers you get on the sides of a pinball machine.
The player buys their pachinko balls and drops them into the loading area. They then start launching the balls, propelling them into the play area. The play area looks rather like that on a pinball machine, with a pattern of upright pins and a number of pockets or gates into which the balls can fall.
Vintage machines use a spring loaded metal flipper or lever to launch the balls. But modern machines fire the balls electronically. The player turns a dial that just controls the frequency with which they are launched.
Once launched the balls bounce around the playing area, hitting against the pins. Unlike in pinball, where the player can bat the ball around the play area using the flippers, in pachinko the player has no control at all over what happens to a ball once it has been launched.
Usually the ball will fall through the pins to the bottom. But sometimes it falls into one of the winning pockets. This gives the player a number of extra balls.
Most modern machines include a slot 918kiss which is triggered if a ball falls into a particular pocket. It is this game that gives the big jackpot wins, that is, large numbers of extra balls.
Players can choose to use the balls they win to keep playing, or exchange them for tokens or prizes such as pens or cigarette lighters. In Japan, cash gambling is illegal, so cash prizes cannot be awarded. To circumvent this, the tokens can usually be taken to a convenient exchange centre – generally located very close by, maybe even in a separate room next to the pachinko parlor.
As you can tell, there is very little skill involved in pachinko, especially in the modern machines where the only thing the player controls is the frequency with which the balls are shot onto the playing area. Apart from that it is purely a game of chance!