Doubled-pawns annotation symbol

Doubled pawns are pawns of the same color occupying one file. They normally arise when a pawn captures onto a file that already contains a friendly pawn. Because one stands behind the other, they cannot advance side by side and often need outside support.

⯼ is the specialized character in Unicode, the standard that assigns common codes to digital characters, for this structure. ⡁ is an earlier rendering that still appears in some databases. Within the symbol system, the glyph marks the structure without yet declaring it good or bad.

Scid vs. PC lists $191 as a suggested value for doubled pawns. It is a Numeric Annotation Glyph (NAG) beyond the meanings assigned by the original Portable Game Notation (PGN) specification, the text format for storing games, and rendering depends on the program. Doubled pawns are often targets and may struggle to create a passed pawn, but they can also control useful squares, open lines through the capture that created them, or provide a semi-open file. The full position decides their value.