The four sides to a dreidel. Some dreidel's use a different fourth letter depending on where they are used. The most common combinations of letters are the nun, gimmel, hay, shin combination. Those Hebrew words represents Nes Gadol Hayah Sham meaning "A great miracle happened there."
There is a special dreidel used only in Israel. Three of the letters are the same but one is different. Its four letters are nun, gimmel, hay, and phay. Notice on this dreidel the shin is replaced with the letter phay. This changes the wording the letters represent to "a great miracle happened here" with the here meaning Israel.
There are different variations of the dreidel game. Here is one.
Start with 2 to 5 players sitting around a hard surface like a floor or table. Give each player ten (this number can vary, the lower the number the faster the game is over) of something. It could be pennies but if you don't want to gamble you can use beans or candy or something else. Have each player contribute two of whatever you are playing with to the main pot to get it started. Then each player takes a turn spinning the dreidel. It will fall over when it is done spinning and whatever letter is showing will tell you what to do next. When you are out of beans you are out of the game. The game is over when the letter gimmel is spun.
Another variation of this game is simply to time how long the dreidel spins. Whomever spins the longest is the winner. It is also possible to spin the dreidel upside down.
This is the letter gimmel. When the dreidel lands on this letter take the main pile.
This is the letter nun. When the dreidel lands on this letter do nothing.
This is the letter hay. When the dreidel lands on this letter tale half the main pile.
This is the letter shin. When the dreidel lands on this letter give up one of your pile.
This is the letter phay. When the dreidel lands on this letter give up one of your pile.
Read more about the holiday of Hanukkah.