an Entity references as follows:
Bird's Opening (or the Dutch Attack) is a chess opening characterised by the move: 1. f4 Bird's is a standard flank opening. White's strategic ideas involve control of the e5-square, offering good attacking chances at the expense of slightly weakening their own kingside. Black may challenge White's plan to control e5 immediately by playing From's Gambit (1...e5); however, the From Gambit is notoriously double-edged and should only be played after significant study. The Encyclopaedia of Chess Openings assigns two codes for Bird's Opening: A02 (1.f4) and A03 (1.f4 d5).