ECO C00
ECO C00–C99 — Open Games and the French Defense: 1.e4 e6 and 1.e4 e5, from the Italian and Ruy Lopez to the King's Gambit.
42 named opening lines are classified under ECO code C00.
- French Defense — 1.e4 e6
- French Defense: Alapin Gambit — 1.e4 e6 2.d4 d5 3.Be3
- French Defense: Baeuerle Gambit — 1.e4 e6 2.d4 b5
- French Defense: Banzai-Leong Gambit — 1.e4 e6 2.b4
- French Defense: Banzai-Leong Gambit, Pinova Gambit — 1.e4 e6 2.b4 Bxb4 3.e5
- French Defense: Bird Invitation — 1.e4 e6 2.Bb5
- French Defense: Carlson Gambit — 1.e4 e6 2.d4 d5 3.Nf3 dxe4 4.Ne5
- French Defense: Chigorin Variation — 1.e4 e6 2.Qe2
- French Defense: Diemer-Duhm Gambit — 1.e4 e6 2.d4 d5 3.c4
- French Defense: Diemer-Duhm Gambit Accepted — 1.e4 e6 2.d4 d5 3.c4 dxe4
- French Defense: Franco-Hiva Gambit — 1.e4 e6 2.d4 f5
- French Defense: Franco-Hiva Gambit Accepted — 1.e4 e6 2.d4 f5 3.exf5
- French Defense: Franco-Sicilian Defense — 1.e4 e6 2.d4 c5
- French Defense: Hoffmann Gambit — 1.e4 e6 2.d4 d5 3.Qe2 e5 4.f4 exf4
- French Defense: Horwitz Attack — 1.e4 e6 2.b3
- French Defense: Horwitz Attack, Papa-Ticulat Gambit — 1.e4 e6 2.b3 d5 3.Bb2
- French Defense: King's Indian Attack — 1.e4 e6 2.d3
- French Defense: King's Indian Attack, Franco-Hiva Gambit — 1.e4 e6 2.d3 f5
- French Defense: Knight Variation — 1.e4 e6 2.Nf3
- French Defense: Knight Variation, Franco-Hiva Gambit — 1.e4 e6 2.Nf3 f5
- French Defense: La Bourdonnais Variation — 1.e4 e6 2.f4
- French Defense: La Bourdonnais Variation, Reuter Gambit — 1.e4 e6 2.f4 d5 3.Nf3 dxe4
- French Defense: Mediterranean Defense — 1.e4 e6 2.d4 Nf6
- French Defense: Morphy Gambit — 1.e4 e6 2.d4 d5 3.Nh3
- French Defense: Normal Variation — 1.e4 e6 2.d4
- French Defense: Orthoschnapp Gambit — 1.e4 e6 2.c4 d5 3.cxd5 exd5 4.Qb3
- French Defense: Pelikan Variation — 1.e4 e6 2.Nc3 d5 3.f4
- French Defense: Perseus Gambit — 1.e4 e6 2.d4 d5 3.Nf3
- French Defense: Queen's Knight — 1.e4 e6 2.Nc3
- French Defense: Reversed Philidor Formation — 1.e4 e6 2.d3 d5 3.Nd2 Nf6 4.Ngf3 Nc6 5.Be2
- French Defense: Réti-Spielmann Attack — 1.e4 e6 2.g3
- French Defense: Schlechter Variation — 1.e4 e6 2.d4 d5 3.Bd3
- French Defense: St. George Defense — 1.e4 e6 2.d4 a6
- French Defense: St. George Defense, Sanky-George Gambit — 1.e4 e6 2.d4 a6 3.c4 b5
- French Defense: St. George Defense, St. George Gambit — 1.e4 e6 2.d4 a6 3.c4 b5 4.cxb5 axb5
- French Defense: St. George Defense, Three Pawn Attack — 1.e4 e6 2.d4 a6 3.c4
- French Defense: St. George Defense, Traditional Line — 1.e4 e6 2.d4 a6 3.Nf3 b5 4.Bd3 c5 5.c3 Bb7 6.O-O Nf6
- French Defense: Steiner Variation — 1.e4 e6 2.c4
- French Defense: Steinitz Attack — 1.e4 e6 2.e5
- French Defense: Two Knights Variation — 1.e4 e6 2.Nf3 d5 3.Nc3
- French Defense: Wing Gambit — 1.e4 e6 2.Nf3 d5 3.e5 c5 4.b4
- Rat Defense: Small Center Defense — 1.d4 e6 2.e4 d6