`  == Suggestion re ``Notation`` ==  It now reads ``In either algebraic or descriptive chess notation, en passant captures are sometimes denoted by ``e.p.`` or similar, but such notation is not required. In algebraic notation, the move is written as if the captured pawn advanced only one square, for example, bxa3 (or bxa3e.p.) in this example.``  I'd suggest adding a word so that it reads ``... the capturing move is written as if ... .`` I wouldn't want the reader to get the idea that the half-move that made the capture possible is recorded as a one-step pawn advance, e.g. that ``a4`` gets retroactively recorded as ``a3`` if an e.p. capture immediately follows. I found the passage ambiguous upon first reading.   `