SHAKING THE CHESS TREE
Imagine that you could take a few million chess games and
combine them into a single game, one which could show
thousands of variations so you'd see at a glance what moves
have been played in every position. Now imagine that the
game would show you statistics for every move, giving
you information on how often each was played and how
successful each move was for the moving side.
You've just imagined what we call a chess tree. Nearly every
chess program has just such a tree as part of the software
package. And since the tree most often applies to the chess
openings, this tree is usually known as an “opening tree” or
“opening book”.
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