Numeric Annotation Glyphs or NAGs are used to annotate chess games when using a computer, typically providing an assessment of a chess move or a chess position. NAGs exist to indicate a simple annotation in a language independent manner.
NAGs were first formally documented in 1994 by Steven J. Edwards in his Portable Game Notation Specification and Implementation Guide.[1] Within the PGN specification, 256 NAGs are proposed of which the first 140 are defined; the remainder were reserved for future definition.
Introduction edit
A Numeric Annotation Glyph is composed of a dollar sign character ("$") immediately followed by one or more digit characters. Each NAG then has a specific meaning and often a standard typographical representation. The meanings first defined stemmed from the use of specific typographic symbols when annotators were commenting upon chess games; most especially in Chess Informant[2] publications. The objective was to devise an alternative representation of these symbols which could be incorporated in the simple computer file format proposed as the PGN standard. This mechanism allowed often sophisticated typography to be expressed using the simple ASCII character set.
Since its inception there has been no attempt to further formalise or standardise the meaning of the undefined 116 NAGs although PGN editors, such as ChessPad, have variously used these higher glyphs.
| NAG range | Classification |
|---|---|
| $0 | provided for the convenience of software designers as a placeholder value;
should not appear in PGN files and has no typographic representation |
| $1-$9 | Move assessments |
| $10-$135 | Positional Assessments |
| $136-$139 | Time Pressure Commentaries |
| $140+ | not defined |
Standard NAGs edit
| NAG | Meaning | Symbol | Unicode[3] | HTML[4] | Name |
|---|---|---|---|---|---|
| $0 | null annotation | ||||
| $1 | good move (traditional "!") see also Nunn Convention for alternate meanings | ! | U+0021 | ! | single exclamation mark |
| $2 | poor move or mistake (traditional "?") (and Nunn Convention) | ? | U+003F | ? | single question mark |
| $3 | very good or brilliant move (traditional "!!") (and Nunn Convention) | ‼ | U+203C | double exclamation mark | |
| $4 | very poor move or blunder (traditional "??") (and Nunn Convention) | ⁇ | U+2047 | double question mark | |
| $5 | speculative or interesting move (traditional "!?") (and Nunn Convention) | ⁉ | U+2049 | exclamation question mark | |
| $6 | questionable or dubious move (traditional "?!") (and Nunn Convention) | ⁈ | U+2048 | question mark and exclamation mark | |
| $7 | forced move (all others lose quickly) or only move | □ | U+25A1 | □ | white square |
| $8 | singular move (no reasonable alternatives) | ||||
| $9 | worst move | ||||
| $10 | drawish position or even | = | U+003D | = | equal sign |
| $11 | equal chances, quiet position | ||||
| $12 | equal chances, active position | ||||
| $13 | unclear position | ∞ | U+221E | ∞ | infinity |
| $14 | White has a slight advantage | ⩲ | U+2A72 | ⩲ | plus sign above equals sign |
| $15 | Black has a slight advantage | ⩱ | U+2A71 | ⩱ | equals sign above plus sign |
| $16 | White has a moderate advantage | ± | U+00B1 | ± | plus-minus sign |
| $17 | Black has a moderate advantage | ∓ | U+2213 | ∓ | minus-or-plus sign |
| $18 | White has a decisive advantage | + − | U+002B U+002D | + -[a] | plus sign, hyphen-minus sign |
| $19 | Black has a decisive advantage | − + | U+002D U+002B | - + | hyphen-minus sign, plus sign |
| $20 | White has a crushing advantage (Black should resign) | ||||
| $21 | Black has a crushing advantage (White should resign) | ||||
| $22 | White is in zugzwang | ⨀ | U+2A00 | ⨀ | N-ary circled dot operator |
| $23 | Black is in zugzwang | ||||
| $24 | White has a slight space advantage | ||||
| $25 | Black has a slight space advantage | ||||
| $26 | White has a moderate space advantage | ○ | U+25CB | ○ | White circle |
| $27 | Black has a moderate space advantage | ||||
| $28 | White has a decisive space advantage | ||||
| $29 | Black has a decisive space advantage | ||||
| $30 | White has a slight time (development) advantage | ||||
| $31 | Black has a slight time (development) advantage | ||||
| $32 | White has a moderate time (development) advantage | ⟳ | U+27F3 | clockwise gapped circle arrow | |
| $33 | Black has a moderate time (development) advantage | ||||
| $34 | White has a decisive time (development) advantage | ||||
| $35 | Black has a decisive time (development) advantage | ||||
| $36 | White has the initiative | ↑ | U+2191 | ↑ | upwards arrow |
| $37 | Black has the initiative | ||||
| $38 | White has a lasting initiative | ||||
| $39 | Black has a lasting initiative | ||||
| $40 | White has the attack | → | U+2192 | → | rightwards arrow |
| $41 | Black has the attack | ||||
| $42 | White has insufficient compensation for material deficit | ||||
| $43 | Black has insufficient compensation for material deficit | ||||
| $44 | White has sufficient compensation for material deficit | ⯹ | U+2BF9[5] | ⯹ | equals sign with infinity below |
| $45 | Black has sufficient compensation for material deficit | ||||
| $46 | White has more than adequate compensation for material deficit | ||||
| $47 | Black has more than adequate compensation for material deficit | ||||
| $48 | White has a slight center control advantage | ||||
| $49 | Black has a slight center control advantage | ||||
| $50 | White has a moderate center control advantage | ||||
| $51 | Black has a moderate center control advantage | ||||
| $52 | White has a decisive center control advantage | ||||
| $53 | Black has a decisive center control advantage | ||||
| $54 | White has a slight kingside control advantage | ||||
| $55 | Black has a slight kingside control advantage | ||||
| $56 | White has a moderate kingside control advantage | ||||
| $57 | Black has a moderate kingside control advantage | ||||
| $58 | White has a decisive kingside control advantage | ||||
| $59 | Black has a decisive kingside control advantage | ||||
| $60 | White has a slight queenside control advantage | ||||
| $61 | Black has a slight queenside control advantage | ||||
| $62 | White has a moderate queenside control advantage | ||||
| $63 | Black has a moderate queenside control advantage | ||||
| $64 | White has a decisive queenside control advantage | ||||
| $65 | Black has a decisive queenside control advantage | ||||
| $66 | White has a vulnerable first rank | ||||
| $67 | Black has a vulnerable first rank | ||||
| $68 | White has a well protected first rank | ||||
| $69 | Black has a well protected first rank | ||||
| $70 | White has a poorly protected king | ||||
| $71 | Black has a poorly protected king | ||||
| $72 | White has a well protected king | ||||
| $73 | Black has a well protected king | ||||
| $74 | White has a poorly placed king | ||||
| $75 | Black has a poorly placed king | ||||
| $76 | White has a well placed king | ||||
| $77 | Black has a well placed king | ||||
| $78 | White has a very weak pawn structure | ||||
| $79 | Black has a very weak pawn structure | ||||
| $80 | White has a moderately weak pawn structure | ||||
| $81 | Black has a moderately weak pawn structure | ||||
| $82 | White has a moderately strong pawn structure | ||||
| $83 | Black has a moderately strong pawn structure | ||||
| $84 | White has a very strong pawn structure | ||||
| $85 | Black has a very strong pawn structure | ||||
| $86 | White has poor knight placement | ||||
| $87 | Black has poor knight placement | ||||
| $88 | White has good knight placement | ||||
| $89 | Black has good knight placement | ||||
| $90 | White has poor bishop placement | ||||
| $91 | Black has poor bishop placement | ||||
| $92 | White has good bishop placement | ||||
| $93 | Black has good bishop placement | ||||
| $94 | White has poor rook placement | ||||
| $95 | Black has poor rook placement | ||||
| $96 | White has good rook placement | ||||
| $97 | Black has good rook placement | ||||
| $98 | White has poor queen placement | ||||
| $99 | Black has poor queen placement | ||||
| $100 | White has good queen placement | ||||
| $101 | Black has good queen placement | ||||
| $102 | White has poor piece coordination | ||||
| $103 | Black has poor piece coordination | ||||
| $104 | White has good piece coordination | ||||
| $105 | Black has good piece coordination | ||||
| $106 | White has played the opening very poorly | ||||
| $107 | Black has played the opening very poorly | ||||
| $108 | White has played the opening poorly | ||||
| $109 | Black has played the opening poorly | ||||
| $110 | White has played the opening well | ||||
| $111 | Black has played the opening well | ||||
| $112 | White has played the opening very well | ||||
| $113 | Black has played the opening very well | ||||
| $114 | White has played the middlegame very poorly | ||||
| $115 | Black has played the middlegame very poorly | ||||
| $116 | White has played the middlegame poorly | ||||
| $117 | Black has played the middlegame poorly | ||||
| $118 | White has played the middlegame well | ||||
| $119 | Black has played the middlegame well | ||||
| $120 | White has played the middlegame very well | ||||
| $121 | Black has played the middlegame very well | ||||
| $122 | White has played the ending very poorly | ||||
| $123 | Black has played the ending very poorly | ||||
| $124 | White has played the ending poorly | ||||
| $125 | Black has played the ending poorly | ||||
| $126 | White has played the ending well | ||||
| $127 | Black has played the ending well | ||||
| $128 | White has played the ending very well | ||||
| $129 | Black has played the ending very well | ||||
| $130 | White has slight counterplay | ||||
| $131 | Black has slight counterplay | ||||
| $132 | White has moderate counterplay | ⇆ | U+21C6 | ⇆ | leftwards arrow over rightwards arrow |
| $133 | Black has moderate counterplay | ||||
| $134 | White has decisive counterplay | ||||
| $135 | Black has decisive counterplay | ||||
| $136 | White has moderate time control pressure | ||||
| $137 | Black has moderate time control pressure | ||||
| $138 | White has severe time control pressure / zeitnot | ⨁ | U+2A01 | ⨁ | n-ary circle plus operator |
| $139 | Black has severe time control pressure / zeitnot |
Non-standard NAGs edit
| NAG | Used by | Meaning | Symbol | Unicode[3] | HTML[4] | Name |
|---|---|---|---|---|---|---|
| $140 | ChessPad[6] | With the idea... | ∆ | U+2206 | increment | |
| $141 | ChessPad[6] | Aimed against... | ∇ | U+2207 | nabla | |
| $142 | ChessPad[6] | Better is... | ⌓ | U+2313 | ⌓ | segment |
| $143 | ChessPad[6] | Worse is... | <= | less than, equal to | ||
| $144 | ChessPad[6] | Equivalent is... | == | equal to, equal to | ||
| $145 | ChessPad[6] | Editorial comment | RR | capital R, capital R | ||
| $146 | ChessPad[6] | Novelty | N | capital N | ||
| $147–$219 | Not defined | |||||
| $220 | ChessPad[6] | Diagram | ⬒ (UI only) | |||
| $221 | ChessPad[6] | Diagram (from Black) | ⬓ (UI only) | |||
| $222–$237 | Not defined | |||||
| $238 | ChessPad[6] | Space advantage | ○ | U+25CB | ○ | white circle |
| $239 | ChessPad[6] | File (columns on the chessboard labeled a-h) | ⇔ | U+21D4 | ⇔ | left right double arrow |
| $240 | ChessPad[6] | Diagonal | ⇗ | U+21D7 | ⇗ | north east double arrow |
| $241 | ChessPad[6] | Centre | ⊞ | U+229E | ⊞ | squared plus |
| $242 | ChessPad[6] | King-side | ⟫ | U+27EB | ⟫ | right double angle bracket |
| $243 | ChessPad[6] | Queen-side | ⟪ | U+27EA | ⟪ | left double angle bracket |
| $244 | ChessPad[6] | Weak point | ✕ | U+2715 | multiplication x | |
| $245 | ChessPad[6] | Ending | ⊥ | U+22A5 | ⊥ | up tack |
| $246 | ChessPad[6] | Bishop pair | CA Chess font: white square with white square to northeast | |||
| $247 | ChessPad[6] | Opposite Bishops | CA Chess font: white square with black square to northeast | |||
| $248 | ChessPad[6] | Same Bishops | CA Chess font: black square with black square to northeast | |||
| $249 | ChessPad[6] | Connected pawns | ⯺ | U+2BFA[5] | ⯺ | united symbol |
| $250 | ChessPad[6] | Isolated pawns | ⯻ | U+2BFB[5] | ⯻ | separated symbol |
| $251 | ChessPad[6] | Doubled pawns | ⯼ | U+2BFC[5] | ⯼ | doubled symbol |
| $252 | ChessPad[6] | Passed pawn | ⯽ | U+2BFD[5] | ⯽ | passed symbol |
| $253 | ChessPad[6] | Pawn majority | text | |||
| $254 | ChessPad[6] | With | ∟ | U+221F[5] | ∟ | right angle |
| $255 | ChessPad[6] | Without | ⯾ | U+2BFE[5] | ⯾ | reversed right angle |
Notes on tables edit
- Some of the symbols are not rendered by some browsers
- The more exotic symbols used by Chess Informator[2] are often derived from common mathematical typographic symbols; their mathematical meaning rarely has any relevance to their chess meaning
- The entries in the Unicode column are, respectively, the decimal and hexadecimal reference for the character or symbol
- The entries in the HTML column are named HTML entities for representing the symbol or character; the Unicode numeric value can always be used where a specific entity does not exist. For example, the left right double arrow ($239) can be represented as either Unicode decimal ⇔ (⇔) or Unicode hexadecimal ⇔ (⇔) or HTML ⇔ (⇔). Unless explicitly noted, the Unicode representation can be interpreted as a default.
See also edit
Notes edit
- ^ Unicode has a minus sign (U+002D, −), but is seldom used
References edit
- ^ "Formal PGN File Specification:section 8.2.4 defines 256 NAGs while section 10 identifies first 140 NAGs". 1994. Retrieved 1 Oct 2016.
- ^ a b "Chess Informant: System of Signs". Archived from the original on 2017-01-01. Uses FigurineCB webfont.
- ^ a b Wood, Alan. "Unicode and multilingual support in HTML, fonts, Web browsers and other applications". www.alanwood.net.
- ^ a b "Character Entity Reference Chart". HTML5 (W3C).
- ^ a b c d e f g "Miscellaneous Symbols and Arrows" (PDF). Character Code Charts (PDF). The Unicode Consortium. 2022. Subsection "Symbols used in chess notation".
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa "ChessPad: a PGN editor". www.wmlsoftware.com.
Sources edit
Krogius, N; Livsic, A; Parma, B; Tajmanov, M. Encyclopedia of Chess Middlegames. (1980) Belgrade: Chess Informant. ISBN 0-7134-3474-0
Malanovic, Aleksander (Editor) Encyclopedia of Chess Openings, volumes A-E. (1978) Belgrade: Chess Informant. ISBN 0-7134-1044-2