Anyone who has even been curious about the game of Go should try this interactive tutorial. Wikibooks also has an introduction, though it does not seem to have been fully written yet. The game is an attractive looking and tricky one, as employed as a dramatic device in the film A Beautiful Mind. Notably, Go is also a game in which the best human players can consistently beat very powerful computers. Unlike chess, it would appear, sheer number crunching ability is not enough to succeed at Go.
Normally played on a grid of 19×19 intersecting lines, the objectives of Go are to capture enemy stones, while also surrounding terrain. Players take turns placing stones on the board, in any position except one where the stone would be immediately captured. Stones or groups of stones that are encircled, such that there are no clear paths or ‘liberties’ extending from them, are captured. Finally, a player may not make a move that would return to the board to how it was immediately before their opponent’s last move (the ‘ko’ rule). The rules according to which stones are placed are very simple, making it initially surprising that the complexity of the game can be so great. Eventually, the game ends when both players pass their turn, indicating that neither sees a possibility for further gains.
As a beginner, playing on a 13×13 board is recommended. The standard size board has more than twice as many intersections to contest, and is probably too much for someone without a developed sense of the game to manage. Learning how to play decently is one project that I will need to suspend, until more pressing tasks are complete.