There are several formats of lottery. The prize can be in cash or in goods. If the organizer doesn't sell enough tickets, he takes a big risk. The prize can be also a fixed percentage of the receipts.

To play National Lottery you have to select 6 numbers or, in case you can't decide the numbers to pick, the computer will pick 6 random numbers for you.

The chances you have of winning a lottery jackpot are determined by different factors such as: the count of possible numbers, etc.