Editing Chess (section)

====Opening====
{{Main|Chess opening}}
{{Chess diagram  
|tright
|
|rd|nd|bd|qd|kd|bd|  |rd
|  |pd|  |  |pd|pd|pd|pd
|pd|  |  |pd|  |nd|  |  
|  |  |  |  |  |  |  |  
|  |  |  |nl|pl|  |  |  
|  |  |nl|  |  |  |  |  
|pl|pl|pl|  |  |pl|pl|pl
|rl|  |bl|ql|kl|bl|  |rl
|The [[Sicilian Defense, Najdorf Variation|Najdorf Variation]] (5...a6), a popular line of the [[Sicilian Defense]] (1...c5), itself a response to the [[King's Pawn Game]] (1.e4)
}}
Competitive players typically learn, memorize, and play well-documented sequences of opening moves. The most common starting moves for White are '''1.e4''' and '''1.d4''', which usually lead to substantially different types of positions, and Black has multiple viable responses to both.

Sequences of opening moves are referred to as ''openings'' and are catalogued in reference works, such as the ''[[Encyclopaedia of Chess Openings]]''. There are thousands of openings, though only a small fraction of them are commonly played; variations of openings may also be given names. Openings vary widely in character from quiet {{chessgloss|positional play}} (for example, the [[Réti Opening]]) to {{chessgloss|sharp}} aggressive play (like the [[Latvian Gambit]]). In some opening lines, the exact sequence considered best for both sides has been worked out to more than 30 moves.<ref>{{harvp|Tamburro|2010|p=18}}</ref>

The fundamental strategic aims of most openings are similar:<ref>{{harvp|Tarrasch|1987}}</ref>
* ''Development:'' moving pieces (particularly bishops and knights) forward to squares on which they are useful (defending, attacking, and controlling important squares) and/or have the potential to take part in future plans and ideas.
* ''Control of the {{chessgloss|center}}:'' control of the central squares allows pieces to be moved to any part of the board relatively easily, and can inhibit the mobility of the opponent's pieces.
* ''King safety:'' typically secured by castling; incorrectly timed castling can be wasteful or even harmful, however.
* ''[[Pawn structure]]:'' players strive to avoid the creation of pawn weaknesses such as isolated, doubled, or backward pawns&nbsp;– and to force such weaknesses in the opponent's position.

Most players and [[Chess theory|theoreticians]] consider that White, by virtue of the [[Initiative (chess)|initiative]] granted from moving first, [[First-move advantage in chess|begins the game with a small advantage]].<ref>{{harvp|Evans|1958|p=175}}</ref> Black usually strives to neutralize White's advantage and achieve {{chessgloss|equality}}, or to develop {{chessgloss|dynamic}} {{chessgloss|counterplay}} in an unbalanced position.