The four squares in the middle of the board (typically the e4, d4, d5, and e5 squares). The center can be described as the literal center (the four squares mentioned before) or it can extend to the squares f4, e4, d4, c4, c5, d5, e5, and f5). A chart showing how each player did in each round.
An arrangement of the results of every game in a tournament in tabular form. The names of the players run down the left side of the table in numbered rows. The names may be listed in order of results, alphabetically, or in pairing order, but results order is most common. The columns are also numbered, each one corresponding to the player in the same numbered row. Each table cell records the outcome of the game between the players on the intersecting row and column, using 1 for a win, 0 for a loss, and ½ for a draw. (In a double round-robin tournament each cell contains two entries, as each pair of players plays two games alternating white and black.) Every game is recorded twice, once from the perspective of each player. The diagonal cells that correspond to the player playing himself are marked with a * or other symbol as they are not used. For examples see Hastings 1895 chess tournament, Nottingham 1936 chess tournament, and AVRO tournament.
The set of openings played by a particular player. The breadth of different players' repertoires varies from very narrow to very broad. For example, a player who always opens with 1.e4 always meets 1.e4 with the Sicilian Defence, and the Najdorf Variation of it if allowed and always meets 1.d4, 1.c4, or 1.Nf3 with 1...f5, intending to play the Dutch Defence, has a very narrow opening repertoire. Bent Larsen, who opened at various times with 1.e4, 1.d4, 1.c4, 1.f4, 1.Nf3, 1.b3, and 1.g3, and played a large number of different defenses as Black, had a very broad opening repertoire. A number reflecting the approximate rating level at which a player performed in a particular tournament or match. It is often calculated by adding together the player's performances in each individual game, using the opponent's rating for a draw, adding 400 points to the opponent's rating for a win, and subtracting 400 points from the opponent's rating for a loss, then dividing by the total number of games. For example, a player who beat a 2400-rated player, lost to a 2600, drew a 2500, and beat a 2300, would have a performance rating of 2550 (2800 + 2200 + 2500 + 2700, divided by four).