The goal
International draughts is played on a 10×10 board, on the dark squares only. Each player starts with 20 pieces. White moves first. You win when your opponent has no pieces left or no move left.
Moving
A piece (a man) moves one square diagonally forward onto an empty square. Tap your piece, then the square where it goes.
Capturing
Jump over an opponent's piece next to you onto the empty square behind it, and it's taken. Men capture forward and backward. If you can keep jumping, you must: one move can take many pieces.
Capturing is compulsory, and you must take the most pieces possible. When you have to capture, your pieces that can do it glow.
Kings
A man that ends its move on the far row becomes a king (gold crown). Kings fly: they move and capture along a whole diagonal, as far as they like.
Draws
The game is a draw if the same position comes back 3 times, after 25 moves each with only kings moving and no capture, or in the classic short king endgames. You can also agree a draw.
Clocks & rating
Timed games use a Fischer increment — you gain a few seconds back after each move. Ranked games (online & matchmaking) adjust your ELO rating; casual computer games never do.
Analyze tab
During games against the computer, the Analyze tab shows a live evaluation bar and what's happening on the board.