Competitive chess has a language entirely different from casual play. If you want to play in tournaments (online or Over-the-Board), you need to understand how pairings work, how to read the clock rules, and what to do if a dispute arises.
The most common tournament format. It is non-elimination. Winners play winners, and losers play losers. You play every round regardless of your score.
Round Robin Elite
A format where every player plays every other player exactly once (or twice). Used in elite events like the Candidates Tournament.
One strong player (Master) plays against many opponents at once, moving from board to board.
Quad Club
A mini Round Robin tournament with exactly 4 players of similar rating. You play 3 games.
Bye Scoring
Full-Point Bye: Given when there is an odd number of players (you have no opponent, you get 1 point free).
Half-Point Bye: A requested break. You ask to skip a round and get 0.5 points (usually limited to early rounds).
A method to break ties. It adds up the scores of all your opponents. If your opponents scored higher, your wins are worth "more" because you faced tougher competition.
A temporary rating calculated based only on your performance in a specific tournament. You can be rated 1500 but have a TPR of 2200 if you beat Grandmasters.
Armageddon Tiebreak
A sudden-death game to decide a winner. White gets more time (e.g., 5 mins) than Black (e.g., 4 mins), but Black has "draw odds"—if the game is drawn, Black wins the match.
Time added to your clock after every move (e.g., +30 seconds). You can build up time if you play fast.
Delay (Bronstein) Buffer
The clock waits a few seconds (e.g., 5s) before counting down. You cannot build up extra time, but you have a safety buffer for every move.
Sudden Death Format
A time control with no increment. When your clock hits 0:00, you lose immediately.
A rule forbidding players from offering a draw before a certain move number (usually move 30) to prevent short, boring games.
If you touch a piece, you must move it (if legal). If you touch an opponent's piece, you must capture it.
J'adoube Etiquette
French for "I adjust." The phrase you must say before touching a piece just to center it on the square.
Arbiter (TD) Official
The referee of the tournament. They resolve disputes, check for illegal moves, and enforce the rules.
Adjournment Historical
Pausing a game to be continued the next day. Rarely used now due to computers, but famously involved a "Sealed Move" placed in an envelope.