classic:

Try to mark the targets 15-20 and Bull three times each, with as little darts as possible. 
A Double hit counts for two marks and a triple hit for three marks.

 

scoring:

you have 3 darts on each target from 15-20 and bull. single=1 point, double=2 points and triple=3points.
try to reach so many points as possible. Maximum is 63 Points.