1. Reading Chess Moves

Every square has a name, and the name never changes. The eight columns are files, lettered a to h from White's left. The eight rows are ranks, numbered 1 to 8 starting at White's side. A square is its file letter and then its rank number, always in that order: the highlighted column is the e-file, the highlighted row is the fourth rank, and e4 is where they cross.

Each piece has a symbol, a small picture of itself, and that is how this app writes moves unless you change it: ♔︎ for the king on e1, ♕︎ for the queen on d1, ♖︎ for the rooks on a1 and h1, ♗︎ for the bishops on c1 and f1, and ♘︎ for the knights on b1 and g1. Books and most websites write a capital letter instead: K, Q, R, B and N — N for the knight, because K already belongs to the king. The move and PGN input boxes in this app take those letters too. Pawns get neither, which is how you spot a pawn move at a glance.

Move the white pawn on the e-file two squares forward.

A pawn move is written as the square the pawn lands on, and nothing else. Push the pawn in front of the king two squares forward: it travels from e2 to e4, and the whole move is written e4.

Play the knight to f3.

Black has answered with a pawn to e5. Every move that is not a pawn move is its piece plus the square it arrives on. Bring the knight from g1 to f3: the knight, then f3 for the square — ♘︎f3. With symbols that is ♘︎ and f3, with letters N and f3. To switch between the two, open Settings and pick Symbols or Letters under Move notation.

Two more marks and you can read almost anything. A capture puts an x in front of the square: the white knight on c3 can take the black pawn on a4, and that move is written ♘︎xa4. A move that attacks the enemy king gets a + on the end, and from a4 the knight attacks the black king on c5 — so the move is written ♘︎xa4+. Black has to answer the check, and White is a pawn up.

One knight capture is also a check.

Play it: take the pawn on a4 with the knight. ♘︎xa4+ — the x for the capture, the + for the check. Black must answer the check, and White is a pawn up.

A + says the enemy king is attacked. A # says it is attacked with nothing to be done about it — checkmate, and the game is over on the spot. Here the white rook slides along the eighth rank to h8. The black king on h6 cannot take the rook and cannot block it; g5 and g7 are covered by the white king on f6, h5 and h7 by the rook itself, and the pawn on g6 is defended by that same king. The move is written ♖︎h8#.

Swing the rook to the h-file.

Deliver it. ♖︎h8# is checkmate: White wins, and the # is how the end of a game is written.

Castling moves two pieces at once — the king two squares towards a rook, and that rook to the square the king stepped over — so it cannot be written as one piece and one square. It gets its own notation instead: O-O when the king goes towards the rook on h1, O-O-O when it goes towards the rook on a1. Two O's for the short side, three for the long side. White can play either one in this position.

Take the rook with the pawn and make a queen.

The black rook on g8 has just taken with check, and one white move answers it three times over. A pawn capture names the file the pawn came from instead of a piece, so the pawn on h7 taking on g8 is hxg8. A pawn that reaches the far rank turns into a new piece and the notation says which: =♕︎ for a queen, or =Q in letters. And the new queen, defended by the bishop on e6, leaves the black king on h8 no square to run to: hxg8=♕︎# — capture, promotion and checkmate in one move.

Which square is highlighted?

White plays ♘︎xa4+. What does that tell you, before you even look at the board?