Jankenpon is a popular game all of you have probably played at least once, although maybe not under this name. The english expression usually is “Rock Paper Scissors”, in german you hear “Schere Stein Papier” or “Schnick Schnack Schnuck” and there are many more names in different languages.
It is mostly believed to be originated in early Japan and become popular in Europe in the 19th century (although the traditional “Scissors” was invented about 500 years ago in Italy, it was precede by the throw “Blade” which served the same purpose). In 1842 the “Rock, Paper, Scissor” Club was founded in London, which then moved to Toronto in 1918 and became the “World RPS Society”. The “World RPS Society” holds world championships every year (since 2002) and on their website you can find the fitting motto “serving the needs of decision makers since 1918”.
Although the origin can not definitely be proven the rules are virtually the same everywhere. There are three different moves. Rock (Guu – ぐう), Scissors (Chyoki – ちょき) and Paper (Paa – パー) with Rock beating Scissors, Scissors beating Paper and Paper beating Rock. As far as I know there is no particular pattern in which to speak in german while playing, probably similar to the game in english you would just count “1, 2, 3” or use the term “Schnick, Schnack, Schnuck”. Also you would usually use this to decide between two people.
In Japan it is not only used for larger groups as well, but it follows certain steps or rules. It starts with your hand as a fist and you say “Saisho wa guu (最初はぐう)” which means “Stone comes first”, which is followed by “Janken pon! (じゃんけんぽん！) where you throw your move on the “pon”. If all chose the same or in a large group the chosen moves are spread evenly, someone says “Aiko desho! (あいこでしょ！)” and on the “sho” everyone choses a new move. The “sho” follows as often as it takes to decide a winner or (in a group) till only two moves are left and one part of the group clearly loses (the rest of the group continues).
Jankenpon is a very popular choice to decide small and large matters alike. In 2011 the second segement of the Fuji Terebi 世にも奇妙な物語 (Yo ni mo kimyou na monogatari) had Janken as topic. The hero (Miura Haruma – 三浦春馬) seems to be one of the worst Janken Players ever and loses every match, be it to decided who has to buy drinks for everyone or who gets the last Bentô. One evening he stumbles upon the “Janken Dojo” and the Master, who teaches him the way of Janken. Suddenly he wins matches and seems to get stronger, but the Master is attacked and dies. Naturally the hero trains even harder and is asked to participate in a Janken Duel that will decide the fate of his entire company. His opponent is no one less than the evil assassin of the Master and the hero defeats him in the most dramatic Janken Showdown ever seen on TV… While the Show is quite dramatic, it really was amusing and I would recommend to watch this short episode if you have time.
Sometimes even more “serious” matters are decided by Janken. In the early days of Arashi (嵐) they were asked who were their leader and they hadn’t decided yet. Although Everyone else wanted Ohno to be the leader, he wanted Sho to be it and the host of the show made them decide it by Janken right away. So it was decided and was never changed.
Another popular pop group in Japan right now is AKB48, which has held several “Single Janken Senbatsu Taikai“, the most recent being the 34th Taikai on September 18th 2013. It’s a tournament of Janken where most of the girls from AKB48 as well as other groups (SKE48, NMB48, etc.) battle till only one winner is left. The best of the girls are featured in the next single and for the fans it’s a big event to watch and cheer for their favorite members.
I think it’s save to say that Janken is suitable for every situation and can be a lot of fun (if you don’t take it too seriously).