Probably the most famous of all darting games.
Each player throws 3 darts in turn with the aim of hitting 1-20 in order, then outer and inner bull to finish. If a player hits what they are aiming for with all three darts, they have another turn.
Variations
If a treble is hit, you skip 2 numbers. For example, if you are on 5 and hit the treble, you miss out 6 and 7 and move straight onto 8. If you hit a double, you skip 1 number.
For the better players among you, play for doubles and trebles only with the previous variation not applying.