The Alapin Sicilian is a chess opening that begins with the moves 1. e4 c5 2. c3. This opening is named after the Russian chess player Semyon Alapin, who popularized it in the late 19th and early 20th centuries.

The Alapin Sicilian is considered a strong sideline variation of the Sicilian Defense, which is one of the most popular and well-studied openings in chess. The Sicilian Defense is a response to white's opening move of 1. e4, and it is characterized by black's move of c5, which aims to control the central squares and create a pawn chain on the queenside.

The Alapin Sicilian is considered to be a solid and flexible opening for white. The main idea behind white's move of c3 is to support the pawn break d4, which will gain space and a lot of activity for white.

Black has several options to counter white's plan in the Alapin Sicilian. One common option is to play Nf6 in this position, aiming to counterattack the e4 pawn. Alternatively, a common option is d5 with a similar idea. Learn how to deal with both of these main moves, and the other sideline options in the video about the Alapin, or the PGN provided.

Overall, the Alapin Sicilian is a solid and flexible opening for white that aims to control the center and develop the pieces quickly. It can be a good choice for players who prefer a unique, and rarer approach to the game, while keeping tactical and positonal ideas in tact.