11623 Players currently online!
Man vs. Machine - good luck!
Turn-based games at any time!
Vote for the best move to win!
Do you have what it takes?
Sharpen your tactical vision!
Get advice and game insights!
Learn from top players & pros!
View millions of master games!
Your virtual chess coach!
Perfect your opening moves!
Test your skills vs. computer!
Find the right private coach!
Can you solve it each day?
Bring it all together!
Beginners, start here!
Make friends & play team games!
News from the world of chess!
Search all Chess.com members!
Find local clubs & events!
Who's the best of your friends?
Read what members are saying!
How are the openings classified? As in, what does the 'A' stand for in A27 or the '16' in C16?
A00 [Start position] A10 [English] 1.c4 A20 [English: King's (1...e5)] 1.c4 e5 A30 [English: Symmetrical] 1.c4 c5 A40 [Queen's Pawn Game] 1.d4 A50 [Indian: 2.c4] 1.d4 Nf6 2.c4 A60 [Benoni: 3.d5 e6] 1.d4 Nf6 2.c4 c5 3.d5 e6 A70 [Benoni: Classical] 1.d4 Nf6 2.c4 c5 3.d5 e6 4.Nc3 exd5 5.cxd5 d6 6.e4 g6 7.Nf3 A80 [Dutch] 1.d4 f5 A90 [Dutch: 2.c4 Nf6 3.g3 e6] 1.d4 f5 2.c4 Nf6 3.g3 e6
Seems pretty random, B's and C's are kingpawn games
The only thing I know is the variations of one opening usually have the same letter... Otherwise I barely see logic in it.
Even I don't see the logic in it...
Btw.. A00 is the Ware opening AND the Amar opening, not the starting position, and both are completely different openings.
ECO openings is a system which is used to go systematical through the openings.
For that, we used A-E, to classify the starting moves. The 1-99 after the letter is where it is in the system. A big opening, lets say ruy lopez (1: e4 e5 2: Nf3 Nc6 3: Bb5) got alot of numbers, because it is a big opening. A lesser opening got less numbers because that there is not so many sidelines.
Openings not starting with 1: e4 or 1: d4 (english, birds and so on) (A00-39)
1: d4 without by 1: .. d5 or 1: .. Nf6. (A40-44)
1: d4 Nf6 without 2: c4 (A45-49)
1: d4 Nf6 2: c4 without g6 or e6. (A50-79)
1: d4 f5 (A80-99)
1: e4 without 1: e6, e5 or c5 (B0-19)
1: e4 c5 (B20-99) (A classic example of extremely big opening)
1: e4 e6 (C0-19)
1: e4 e5 (C20-99)
1: d4 d5 (D0-69)
1: d4 Nf6 2: c4 g6 with d5 grünfeld (D70-99)
1: d4 Nf6 2: c4 e6 (E0-59)
1: d4 Nf6 2: c4 g6 (without d5) (E60-99)
That's rather complicated, and not easy to understand at all...
Why are there so many variations anyways? And how do they arise?
Chess players and their famous counterparts
by tkbunny a few minutes ago
So? You Wanna Play me? . . . . For I am DEATH! . . .
by DrSpudnik a few minutes ago
Why does nobody play 1. c3?
by Sqod 4 minutes ago
Syzygy Tablebases + Chessbase 12/Deep Fritz 14
by MrEdCollins 8 minutes ago
by 1NaturalDisaster 8 minutes ago
Trailer for Pawn Sacrifice
by stuzzicadenti 8 minutes ago
Are tactics really the way to go?
by ponz111 8 minutes ago
When did USCF take away 100 rating points from everybody?
by fryedk 12 minutes ago
What do you say one move from mating your opponent!
by rtr1129 13 minutes ago
What other interests do you have apart from Chess?
by Ziryab 14 minutes ago
Why Join | Chess Topics |
Help & Support |
© 2015 Chess.com
• Chess - English
We are working hard to make Chess.com available in over 70 languages. Check back over the year as we develop the technology to add more, and we will try our best to notify you when your language is ready for translating!