Openings
Chess Opening Principles Every Player Should Know
You do not need to memorize opening theory to play the first ten moves well. A handful of principles, followed consistently, will give you a healthy position in almost every game. They are not laws, and strong players break them when there is a concrete reason, but if you are unsure what to play, these rules will point you to a good move far more often than not. Below each principle is explained with real move sequences, including a few well-known traps that show what happens when a principle is ignored.
1. Fight for the center
The four central squares, e4, d4, e5 and d5, are the most valuable on the board. A piece in the center controls more squares and can move to either wing quickly. A knight on e4 attacks up to eight squares; a knight on a1 attacks two. That is why the most popular first moves are 1.e4 and 1.d4: they occupy the center with a pawn and open lines for the bishops and queen.
Controlling the center does not always mean occupying it. In the Sicilian Defense, 1...c5 controls d4 from the side, and in many openings a fianchettoed bishop on g7 or b7 pressures the center from a distance. The point is that your pieces and pawns should have a say about what happens in the middle of the board.
2. Develop your pieces, knights before bishops
Development means moving your pieces off their starting squares to useful posts. In the opening, every move should ideally bring a new piece into play. Knights usually go out first because their best squares (f3, c3, f6, c6) are obvious, while the best squares for bishops often depend on how the pawns are set up.
A model start is 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.c3 Nf6 5.d3 d6 6.O-O O-O. In six moves each side has developed both knights and one bishop, castled, and made only the pawn moves needed to open lines and support the center.
Compare that with a beginner game where one side plays a3, h3, a4 and h4 in the first six moves. Those pawn moves do almost nothing, and the opponent will simply be several pieces ahead in development when the fighting begins.
3. Do not move the same piece twice without a reason
Every tempo in the opening is precious. If you move a knight to g5, then back to f3, then out to h4, you have used three moves to develop one piece. Moving a piece twice is fine when you win material, avoid a threat or gain something concrete, but "it looked active" is not a good reason.
The Blackburne Shilling Gambit, 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nd4, breaks this rule on purpose as a trap. Against correct play, such as 4.Nxd4 exd4 5.O-O, Black has simply wasted time. The trap only works if White grabs the e5 pawn, which you can see in our Italian Game guide.
4. Do not bring the queen out too early
The queen is your most valuable piece, so when it comes out early, your opponent can develop with tempo by attacking it. Each time you move the queen away, your opponent gets a free developing move.
The classic example is the Scholar's Mate attempt. After 1.e4 e5 2.Bc4 Nc6 3.Qh5, White threatens Qxf7 mate. If Black does not see it and plays 3...Nf6?? then 4.Qxf7# ends the game.
Play through Scholar's Mate →But if Black defends correctly with 3...g6, the queen has to move again: 4.Qf3 Nf6 and now Black has two knights developed while White's queen has used three of White's four moves. Black can follow with ...Nd4 hitting the queen and c2, gaining even more time. Scholar's Mate wins games against complete beginners, but against anyone who knows the defense it leaves White worse off.
The same principle applies to Black. In the Scandinavian, 1.e4 d5 2.exd5 Qxd5 3.Nc3 the queen is immediately attacked and must move again. Black can still play this opening because the queen has a safe square on a5 or d6, but it costs time, and Black must know where the queen belongs.
5. Castle early
The king is safest behind a wall of pawns in the corner. In the center, it is exposed to checks along the e-file and the diagonals, especially once pawns are exchanged and lines open. Castling also brings a rook toward the center, so it is both a safety move and a development move.
Fool's Mate is the most extreme example of what happens when the king's protection is weakened in the opening: 1.f3 e5 2.g4 Qh4#. White moved the two pawns that shield the king's diagonal, and Black's queen mates in two moves.
See Fool's Mate, the fastest possible checkmate →The lesson is not just "castle." It is also "be careful with the pawns in front of your king," particularly the f-pawn, which in the starting position is defended only by the king.
6. Connect your rooks
Your opening is finished when your minor pieces are developed, your king is castled and your queen has moved off the back rank so that the rooks see each other. Connected rooks can move to open or half-open files, such as the d-file or e-file, where they will be most useful in the middlegame. A common target is to have rooks on d1 and e1 (or d8 and e8) by around move 12 to 15.
A principle-breaking trap: Legal's Mate
Legal's Mate is named after the 18th-century French player Sire de Legal. It punishes a player who pins a knight and assumes the pin is absolute:
1.e4 e5 2.Nf3 d6 3.Bc4 Bg4 4.Nc3 g6? 5.Nxe5! Bxd1?? 6.Bxf7+ Ke7 7.Nd5#.
Black made two errors. The slow 4...g6 ignored development, and 5...Bxd1 grabbed the queen without checking what White was threatening. After 5.Nxe5 Black should play 5...dxe5 6.Qxg4 and accept being a pawn down rather than getting mated. The pin on f3 was only relative because the piece behind the knight was a queen, not the king, and White was willing to give it up.
Play through Legal's Mate →When the rules can be broken
Principles are general guidance. Strong players move the queen early when it wins material, delay castling when the center is closed, and spend extra pawn moves when they gain space. The key question is always concrete: does this move do something useful that the general rule is designed to protect? If you cannot name a specific reason, follow the principle.
Key takeaways
- Put pawns or pieces in the center, or attack it from the side.
- Develop a new piece with nearly every move, knights usually before bishops.
- Avoid moving the same piece twice, and keep the queen home unless it achieves something.
- Castle early, look after the f-pawn, and connect your rooks.
- Before grabbing material in the opening, check every capture and check your opponent has.
- Practice these ideas in games against the computer and with puzzles, then browse specific systems in our openings overview.