GameKnot is an Internet chess server

Internet chess server

An Internet chess server is an external server that provides the facility to play, discuss, and view the board game of chess over the Internet...

 featuring both correspondence chess

Correspondence chess

Correspondence chess is chess played by various forms of long-distance correspondence, usually through a correspondence chess server, through email or by the postal system; less common methods which have been employed include fax and homing pigeon...

 and real-time chess, along with Java

Java (programming language)

Java is a programming language originally developed by James Gosling at Sun Microsystems and released in 1995 as a core component of Sun Microsystems' Java platform. The language derives much of its syntax from C and C++ but has a simpler object model and fewer low-level facilities...

 single-player games, without the need to download additional software. GameKnot has been in business since June 2000, with has over 1 million registered players who have completed over 19 million games as of March 2011. For a typical match, unless two users are simultaneously logged in and committed to playing quickly, games are generally played over a period of days (for example, up to fourteen days per move per person), weeks or even months, and the time constraints resemble a correspondence chess

Correspondence chess

Correspondence chess is chess played by various forms of long-distance correspondence, usually through a correspondence chess server, through email or by the postal system; less common methods which have been employed include fax and homing pigeon...

 match, although players may move more rapidly. Real-time chess (or Blitz) matches are also available. The site offers a wide variety of features, including an extensive database including generally recognized names for chess opening

Chess opening

A chess opening is the group of initial moves of a chess game. Recognized sequences of opening moves are referred to as openings as initiated by White or defenses, as created in reply by Black. There are many dozens of different openings, and hundreds of named variants. The Oxford Companion to...

s, site-sponsored tournaments, player-sponsored mini-tournaments, a site-sponsored league with 18 divisions, two site-sponsored chess ladders, the ability to program conditional moves during a game, the option to declare a vacation to suspend games, and an in-game "analyze board" function that allows players to explore potential moves. It also keeps a record of past games, allowing players to learn from previous wins and losses. GameKnot maintains a ranking system similar to the Elo rating system

Elo rating system

The Elo rating system is a method for calculating the relative skill levels of players in two-player games such as chess. It is named after its creator Arpad Elo, a Hungarian-born American physics professor....

 used by the World Chess Federation

Fédération Internationale des Échecs

The Fédération Internationale des Échecs or World Chess Federation is an international organization that connects the various national chess federations around the world and acts as the governing body of international chess competition. It is usually referred to as FIDE , its French acronym.FIDE...

. As of May 2011, "borissp" tops Gameknot's Top 100 veteran players list with a rating of 2643.

Each player's profile includes information on the Elo rating for that player, percentile for the Elo rating, a graph showing the player's rating over a period of one year, the total number of games won, lost, drawn and played, the number of games in progress, the last time the player was seen on the site, information relating to mini-tournaments and team play, the number and percentage of timeouts, the average time per move, the longest winning and losing streaks for the player, and detailed statistics showing win-loss percentages, the number of moves, trends for all games, games over the last year and games played in the last 90 days. However, players can choose to "hide" their online status, so that the last time they were seen on the site is unavailable to profile viewers.

GameKnot is funded by premium membership fees and paid advertising, with multiple levels of premium memberships to allow users to play more games, and to access many advanced features not available to free account. Teams, clubs, forums and tournaments are also offered, with higher level memberships required for team captains and co-captains. For non-paying players, GameKnot serves banner advertising from several advertising networks (no pop-ups or pop-unders are used however). Non-paying players are limited to a maximum of 12 games at a time (starts at 6, then the limit is increased to 12 as new games are completed).

Concerns

To avoid players with a free account using multiple accounts, GameKnot tracks users by IP address and scans for suspect activity, such as ratings manipulation by accounts playing from the same IP address. Unfortunately, their administration provides for no appeal to players who may play from the same IP address served up by corporate firewalls, making this system less than perfect. Gameknot will often block such users until they pay for premium membership. GameKnot also blocks non-paying users if they are employing ad-blocking software with their web browser, forcing them to pay for premium membership.