Notation - Chess Notation Overview

Notation

Definition

In chess, notation is the standardized system for recording moves and positions so games can be played back, analyzed, taught, and archived. Today, the global standard is algebraic notation (often SAN, Short Algebraic Notation). Game records are commonly stored in PGN (Portable Game Notation), while single positions are encoded with FEN (Forsyth–Edwards Notation). Notation underpins study, coaching, databases, engines, and tournament documentation.

Why chess notation matters (strategic and historical significance)

Notation preserves opening theory, middlegame ideas, and endgame technique, enabling players to compare lines, cite sources, and build repertoires. Historically, descriptive notation (e.g., P-K4) was common in English-language books until the late 20th century, when FIDE’s adoption of algebraic notation accelerated its worldwide use for its clarity and language independence. Notation also supports fair play and regulations: in most OTB time controls (classical and many rapid events), players must keep an accurate scoresheet for possible claims (e.g., threefold repetition, fifty-move rule), adjudications, and appeals.

Core elements of algebraic notation (SAN)

• Squares: a–h files and 1–8 ranks (e.g., e4, c6).
• Pieces: K (king), Q (queen), R (rook), B (bishop), N (knight). Pawns have no letter (e.g., e4 means a pawn moved to e4).
• Captures: “x” (e.g., Bxe5, exd5). En passant may be noted with “e.p.” after the capture in explanatory contexts.
• Checks and mate: “+” for check (Qh7+), “#” for mate (Qh7#). Some older texts show “++” for double check.
• Castling: O-O (king side) and O-O-O (queen side).
• Promotion: “=Q/R/B/N” (e.g., e8=Q+, c1=N#).
• Disambiguation: If two identical pieces can move to the same square, add file, rank, or both (e.g., Nbd2, R1e2, Qh4e1).
• Move numbers and results: “1.” for White’s move, “...” to indicate Black’s reply on a new line; results: 1-0, 0-1, 1/2-1/2.
• Annotations: “!”, “!!”, “!?”, “?!”, “?”, “??” and evaluation symbols like “=” (equal), “+/=” (White is slightly better), “±” (White clearly better), “∓” (Black clearly better), “∞” (unclear).

Variants and related systems

• Short Algebraic (SAN): The most common human-readable form (e.g., Nf3, Bxe5+).
• Long Algebraic (LAN): Includes the origin square (e.g., Ng1-f3, Bf4xe5+), useful for clarity.
• Coordinate move notation: Four-character moves like e2e4, g1f3; used by engines and protocols. Example viewer using SAN moves:
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• Figurine Algebraic: Replaces piece letters with icons, making books language-neutral (e.g., ♞f3). Digital texts often emulate this.
• Descriptive notation (historic): Expresses moves relative to each player’s perspective (e.g., P-K4). Now largely replaced by algebraic.

PGN and FEN: recording games and positions

PGN stores complete games with move text and optional metadata (event, site, date, players, result, ECO, etc.). Inside PGN, Numeric Annotation Glyphs (NAGs) such as $1–$6 correspond to “!”, “?”, “!!”, “??”, “!?” and “?!”. FEN stores a single position (which side to move, castling rights, en passant square, halfmove/fullmove counters) and is foundational for engine and tablebase work.

• Example PGN snippet with SAN and a NAG: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 $1 4. Ba4 Nf6 5. O-O Be7 (Ruy Lopez).
• Example FEN after 1. e4 e5 2. Nf3: rnbqkbnr/pppp1ppp/8/4p3/4P3/5N2/PPPP1PPP/RNBQKB1R b KQkq - 1 2.
• Embedded PGN viewer (Scholar’s Mate pattern):
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How notation is used in practice

• Over-the-board: Players keep a scoresheet; it enables claims like Threefold repetition and the Fifty-move rule, and supports post-mortem analysis.
• Training and prep: Coaches annotate with symbols, highlight a Blunder (??) or Interesting move (!?), and mark Book moves and a TN (theoretical novelty).
• Engines and databases: Engines output lines in coordinate or SAN with an Eval (often in Centipawns). Repertoires reference Theory and cite PGNs.
• Publishing and media: Figurine or SAN is used in books, articles, and broadcasts for universal readability.

Examples to visualize

Basic SAN sequence: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Be7. Notice the castle O-O, and that pawns have no letter.

Capture and check: 1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Nxd4 5. Qxd4+ (check by queen).

Disambiguation: From a position with knights on b1 and f3 both able to go to d2, Nbd2 indicates the b1-knight moves; Nfd2 indicates the f3-knight.

Promotion and mate: ... e2 1. e8=Q+ or 1. e8=N# illustrate promotion equality sign and final symbol.

En passant: After White plays 1. e4 and Black 1... d5, 2. exd5 e.p. (explanatory) is a capture en passant when applicable.

Common annotation symbols (human-readable and NAGs)

• !! ($3) – brilliant move; ! ($1) – good move.
• !? ($5) – interesting; ?! ($6) – dubious.
• ? ($2) – mistake; ?? ($4) – blunder.
• Evaluation signs: = (equal), += or ⩲ (slightly better for White), ± (clearly better White), ∓ (clearly better Black), ∞ (unclear), ⨀ (initiative), ∑ (compensation), etc. Conventions vary slightly by publisher.

Tips, pitfalls, and best practices

• Use uppercase “O” (letter O) for castling, not zero: O-O, O-O-O.
• When two identical pieces can reach the same square, include file or rank disambiguation to avoid ambiguity.
• Prefer SAN/LAN in human texts; use coordinate notation (e2e4) when interfacing with engines or protocols.
• Keep PGN clean: results must match board outcome (1-0, 0-1, 1/2-1/2), and metadata tags should be correct for database searchability.
• For diagrams or snapshots, provide a FEN; for studies, you can also give a minimal PGN with a FEN header.

Interesting facts and anecdotes

• Algebraic-style records date back to medieval and Arabic sources; FIDE’s late-20th-century standardization made it truly universal.
• Figurine algebraic helped globalize chess publishing—no translation needed for piece names.
• Engines often output “best move” suggestions alongside evaluation shifts in CP; pairing that with clear SAN annotations can reveal powerful Swindling chances or a hidden Trap.
• Some famous games are identified by a few moves in notation—e.g., the “Game of the Century” with 17...Be6!! (Byrne vs. Fischer, 1956).

Related and deeper reading (internal links)

See: Algebraic notation, PGN, FEN, Annotation, Annotation symbols, Engine, Best move, Blunder, Book, Theory, Perpetual, Zugzwang.

Mini demo PGN with arrows

Ruy Lopez opening moves visualized (SAN):

1. e4 e5 2. Nf3 Nc6 3. Bb5 a6

Viewer embed:
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