Many of the commonly seen opening strategies, joseki and tactical shapes which aid skillful play have been developed over thousands of years of play and taught to successive generations rather than discovered through individual play. There are many positional situations in Go which are recognizable by an experienced player that are hard to recognize otherwise. Once players gain knowledge of these patterns in play, they then must ponder how to apply them in accordance with the position of the board as it stands and the recognizable patterns already in place. Thus, the traditions of Go strategical theory utilized by most stronger players are taught to beginners help to limit the scope of variation in actual play while deepening strategy.