Petanque is extremely simple, just like horseshoes. There's a target, and you have to get as close to it as possible.
What makes it so appealing, is that you can be way ahead for a while, yet lose a second later, or vice versa. Because nothing is decided until the last player plays the very last boule. If he or she moves the target ball or knocks an opponent ball out of the way, the layout of the boules - and thus your score - may change dramatically.