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

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 Groupings
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

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 + -[lower-alpha 1] 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

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 &cir; white circle
$239 ChessPad[6] File (columns on the chessboard labeled a-h) ⇔ U+21D4 &hArr; left right double arrow
$240 ChessPad[6] Diagonal ⇗ U+21D7 &neArr; north east double arrow
$241 ChessPad[6] Centre ⊞ U+229E &boxplus; squared plus
$242 ChessPad[6] King-side ⟫ U+27EB &Rang; right double angle bracket
$243 ChessPad[6] Queen-side ⟪ U+27EA &Lang; left double angle bracket
$244 ChessPad[6] Weak point ✕ U+2715 multiplication x
$245 ChessPad[6] Ending ⊥ U+22A5 &perp; 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] &#x2bfa; united symbol
$250 ChessPad[6] Isolated pawns ⯻ U+2BFB[5] &#x2bfb; separated symbol
$251 ChessPad[6] Doubled pawns ⯼ U+2BFC[5] &#x2bfc; doubled symbol
$252 ChessPad[6] Passed pawn ⯽ U+2BFD[5] &#x2bfd; passed symbol
$253 ChessPad[6] Pawn majority text
$254 ChessPad[6] With ∟ U+221F[5] &#x221f; right angle
$255 ChessPad[6] Without ⯾ U+2BFE[5] &#x2bfe; reversed right angle

Notes on tables

  1. Some of the symbols are not rendered by some browsers
  2. 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
  3. The entries in the Unicode column are, respectively, the decimal and hexadecimal reference for the character or symbol
  4. 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 &#8660; (⇔) or Unicode hexadecimal &#x21D4; (⇔) or HTML &hArr; (⇔). Unless explicitly noted, the Unicode representation can be interpreted as a default.

See also

Notes

  1. ↑ Unicode has a minus sign (U+002D, &minus;), but is seldom used

References

  1. ↑ "Formal PGN File Specification:section 8.2.4 defines 256 NAGs while section 10 identifies first 140 NAGs". 1994. Retrieved 1 Oct 2016.
  2. 1 2 "Chess Informant: System of Signs". Archived from the original on 2017-01-01. Uses FigurineCB webfont.
  3. 1 2 Wood, Alan. "Unicode and multilingual support in HTML, fonts, Web browsers and other applications". www.alanwood.net.
  4. 1 2 "Character Entity Reference Chart". HTML5 (W3C).
  5. 1 2 3 4 5 6 7 "Miscellaneous Symbols and Arrows" (PDF). Character Code Charts (PDF). The Unicode Consortium. 2022. Subsection "Symbols used in chess notation".
  6. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 "ChessPad: a PGN editor". www.wmlsoftware.com.

Sources

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

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.