The opening is determined by both players and the opening name is dependent on what each player does. for example you can't play the dutch defense against 1.e4. When people says stuff like "i play the sicilian" they mean that when they see e5, they will respond with c5 and play whatever type of sicilian they had in mind. Their opponents can also choose how they respond to the sicilian. For example if we play a game, me as white and you as black and it goes...
As you can see we both decide the opening. When someone says they play the sicilian they are just talking about playing the sicilian against e4, rather than the carokann. Of course if white plays d4, they would play a different opening.
I kinda over explained this concept, so i hope i didnt cause more questions
i need to answer someone on this query, and need the best answer:
suppose as white i want to play italian game or ruy lopes. but when i play my first move (1.e4), black does not play 1...e5 and instead plays c5 which is sicilian opening. such things can happen in every game. so can we say that it is black who choses the opening?!
2) secondly even if black plays the first move and second moves as per italian or ruy lopez but after that black makes some other move which is not in line with italian / ruy lopez, then what?
3) even if i had switched to sicilian and responded to 1....c5 by black and we made 2 or 3 moves as per sicilian and then my opponent play a move which is not in line with sicilian, then what?
i have heard players saying "i usually play sicilian......or scandinavian defense.....things like that.... does it mean they only refer to the first move or how far that opening can continue at one's will ?
i will be thankful if someone can deliberate on this.
i would thank if someone can deliberate on this.