Update

chess.md

@@ -116,6 +116,7 @@ Besides similar games such as [shogi](shogi.md) there are many variants of chess
 - **old chess**: The rules of chess itself have been changing over time (e.g. adding the 50 move rule etc.). The older rule sets can be seen as variants as well.
 - **puzzle**: For single player, chess positions are presented and the player has to find the best move or sequence of moves.
 - **racing kings**: The starting position has both players on the same side, the goal is to get one's king to the other side first.
+- **[non-Euclidean](non_euclidean.md)**: different geometries of the board, e.g. [hyperbolic](hyperbolic.md) or [spherical](spherical.md).
 - **3D chess**: [3D](3d.md) generalization of chess.
 - **randomly chosen variant**: Here a chess variant to be played is chosen at random before the game, e.g. by dice roll. { This is an idea I got, not sure if this exists or has a different name. ~drummyfish }
 

go.md

@@ -6,15 +6,17 @@ WIP
 
 { I am still learning the beautiful game of go, please excuse potential unintentional errors here. ~drummyfish }
 
-Go (from Japanese *Igo*, "surrounding board game") is possibly the world's oldest two-player board [game](game.md), which originated in Asia, one of the most beautiful, elegant, deep and popular games of this type in history, whose significance can be compared to that of [chess](chess.md), despite it largely remaining widely popular only in Asia. There however, especially in Japan, go is pretty big, it appears a lot in [anime](anime.md) etc. **Go is a bit difficult to get into** (kind of like [vim](vim.md)?) though the rules can be learned quite quickly; it is hard to make big-picture sense of the rule implications and it may take weeks to months before one can even call himself a beginner player.
+Go (from Japanese *Igo*, "surrounding board game", also *Baduk* or *Wei-qi*) is possibly the world's oldest original-form two-player board [game](game.md), coming from Asia, and is one of the most beautiful, elegant, deep and popular games of this type in [history](history.md), whose cultural significance and popularity can be compared to that of [chess](chess.md), despite it largely remaining widely popular only in Asia (along with other games like [shogi](shogi.md), or "Japanese chess"). There however, especially in Japan, go is pretty big, it appears a lot in [anime](anime.md), there are TV channels exclusively dedicated to go etc. **Go is a bit difficult to get into** (kind of like [vim](vim.md)?) though the rules can be learned quite quickly; it is hard to make big-picture sense of the rule implications and it may take weeks to months before one can even call himself a beginner player. To become a master takes lifetime.
 
-{ There is a nice site hosting everything related to go: Sensei's Library at https://senseis.xmp.net/. ~drummyfish }
+{ There is a nice non-bloated site hosting everything related to go: Sensei's Library at https://senseis.xmp.net/. ~drummyfish }
 
 **Compared to chess** (some purists dislike this, see https://senseis.xmp.net/?CompareGoToChess) the rules of go are much more simple -- which is part of the game's [beauty](beauty.md) (see [easy to learn, hard to master](easy_to_learn_hard_to_master.md)) -- though the emergent complexity of those few rules is grandiose; so much so that to play the game well is usually considered more challenging than learning chess well, as there are many more possibilities and mere calculation is not enough to be strong, one needs to develop a strong intuition; this is also the reason why it took 20 more years for [computers](computer.md) to beat the best humans in go than in chess. Many say that go is yet deeper than chess and that it offers a unique experience that can't be found anywhere else; go is more mathematical, something that just exists naturally as a side effect of logic itself, while chess is a bit of an arbitrary set of more complex rules fine-tuned so that the game plays well. The spirit of go is also more [zen](zen.md)-like and peaceful: while chess simulates [war](war.md) (something more aligned with western mentality), go is more about dividing territory, one could even see it not as a battle but rather a creation of [art](art.md), beautiful patterns (something better aligned with eastern mentality).
 
 **From [LRS](lrs.md) point of view go is one of the best games ever**, for similar reasons to chess (it's highly free, [suckless](suckless.md), cheap, [not owned by anyone](public_domain.md), [fun](fun.md), mathematically deep, nice for programming while the game itself doesn't even require a [computer](computer.md) etc.) plus yet greater [simplicity](minimalism.md) and beauty.
 
-TODO: rating, programming, stats, programs and sites for playing, 4x4 solved variant, ...
+**Solving go:** similarly to chess the full game of go seems unlikely to be solved -- the 19x19 game state tree is yet larger than that of chess, but the much simpler rules possibly give a bigger hope for mathematical proofs. Smaller boards however have been solved: Erik van der Werf made a program that confirmed win for black on boards up to (and including) 5x5 (best first move in all cases being in the middle of the board). Bigger boards are being researched, but a lot of information about them is in undecipherable Japanese/Korean gibberish, so we leave that for the future.
+
+TODO: rating, programming, stats, programs and sites for playing, ...
 
 ## Rules
 
@@ -22,9 +24,9 @@ The rules of go vary a bit more than those of chess, they are not as much unifie
 
 The game's **goal** is basically to surround a bigger territory than the enemy player. The formal rules are pretty simple, though their implications are very complex.
 
-Go is played by a black and white player, black plays first (unlike in chess) and then both players take turns placing stones of one's own color on squares -- a square is the INTERSECTION of the lines on the board, NOT the place between them. The stones are all the same (there are no different types of stones like in chess) and they cannot move; once a stone is placed, it stays on its position until the end of the game, or until it is captured by the enemy player. The board size is **19x19**, but for for students and quick games 13x13 and 9x9 boards are also used. As black plays first, he has a slight advantage; for this white gets bonus points at the end of the game, so called **komi**, which is usually set to be 6.5 points (the half point eliminates the possibility of a draw). Komi may differ depending on board size or a specific scoring systems.
+Go is played by a black and white player, black plays first (unlike in chess) and then both players take turns placing stones of one's own color on squares -- a square is the INTERSECTION of the lines on the board, NOT the place between them (consider the lines to be carved in stone, the intersection is where the stone stands with stability). The stones are all the same (there are no different types of stones like in chess) and they cannot move; once a stone is placed, it stays on its position until the end of the game, or until it is captured by the enemy player. The board size is **19x19**, but for for students and quick games 13x13 and 9x9 boards are also used. As black plays first, he has a slight advantage; for this white gets bonus points at the end of the game, so called **komi**, which is usually set to be 6.5 points (the half point eliminates the possibility of a draw). Komi may differ depending on board size or a specific scoring system.
 
-Any player can **pass** on his move, i.e. making a move isn't mandatory. However you basically always want to make a move, you one only passes when he feels there is nothing more to be gained and the game should end. If both player pass consecutively, the game ends.
+Any player can **pass** on his move, i.e. making a move isn't mandatory. However you basically always want to make a move, one only passes when he feels there is nothing more to be gained and the game should end. If both players pass consecutively, the game ends.
 
 The game considers **4-neighborhoods**, NOT 8-neighborhood, i.e. squares that don't lie on board edges have 4 neighbors: up, right, bottom and left; diagonal squares are NOT neighbors.
 
@@ -38,7 +40,7 @@ The **ko** rule states that one mustn't make a move that returns the board to th
 
 **Prisoners** are enemy's stones that are OBVIOUSLY in your territory and so are practically dead. I.e. they are inside what's clearly not their territory and with further play would clearly be captured. Obvious here is a matter of agreement between players -- if players disagree whether some stones are obvious prisoners, they simply keep playing and resolve the situation.
 
-**Scoring:** there are multiple scoring systems, but the most common seems to be the following. At the end of the game we count the score for black as the size of black's territory PLUS one point for each stone black has captured PLUS one point for each white prisoner in black's territory. Score for black is computed analogously but we also add the komi compensation. The player with more points wins.
+**Scoring:** there are multiple scoring systems, but the most common seems to be the following. At the end of the game we count the score for black as the size of black's territory PLUS one point for each stone black has captured PLUS one point for each white prisoner in black's territory. Score for white is computed analogously but we also add the komi compensation. The player with more points wins.
 
 **Handicaps:** TODO.
 
@@ -67,7 +69,9 @@ TODO
 
 ## Play Tips
 
-## Programming
+TODO
+
+## Go And Computers, Programming
 
 See also https://senseis.xmp.net/?ComputerGoProgramming and https://www.chessprogramming.org/Go.
 
@@ -79,4 +83,9 @@ TODO
 
 Some [interesting](interesting.md) stats about go follow.
 
-The longest possible game without passes has 4110473354993164457447863592014545992782310277120 moves. The longest recorded professional game seems to be mere 411 moves long (Hoshino Toshi vs Yamabe Toshiro, 1950). There are 2.08168199382 * 10^170 legal positions on a 19x19 board, 3.72497923077 * 10^79 for 13x13 and 1.03919148791 * 10^38 for 9x9. The number of possible games is estimated from 10^10^100 to 10^10^171. An average high-level game lasts about 150 moves. Average branching factor is 250 (compare to 35 in chess).
+The longest possible game without passes has 4110473354993164457447863592014545992782310277120 moves. The longest recorded professional game seems to be mere 411 moves long (Hoshino Toshi vs Yamabe Toshiro, 1950). There are 2.08168199382 * 10^170 legal positions on a 19x19 board, 3.72497923077 * 10^79 for 13x13 and 1.03919148791 * 10^38 for 9x9. The number of possible games is estimated from 10^10^100 to 10^10^171. An average high-level game lasts about 150 moves. Average branching factor is 250 (compare to 35 in chess).
+
+## See Also
+
+- [chess](chess.md)
+- [game of life](game_of_life.md)