Your question's answer is written in Go rules : Since the black player starts the game, he has a significant advantage. In order to balance it, a value called komi is subtracted from the black player score. It is 5.5 for a 19x19 board, 4.5 for a 13x13 board and 3.5 for a 9x9 board.
(hide) Tired of placing boats or Espionage pieces at the begining of the game? You can go to Game Editors and save some of your favourite positions for future use. (pauloaguia) (show all tips)