Angry Birds is an iphone game where you use a slingshot to propel exploding birds (yes, really) at various structures containing pigs, which you're trying to kill by hitting directly or by causing the structures to collapse on them.
The funny thing about Angry Birds is that it's actually not a great game in one sense -- while playing the game takes some skill, skill is no guarantee of success.
The trouble is that your only control method, the angle at which the bird is launched from the slingshot, is the input to a chaotic system with sensitive dependence on initial conditions. If you launch the bird at an angle of 72 degrees, it hits a block off to one side and then stops. If you launch the bird at 73 degrees, it hits the same block off to the side a little bit harder, which starts a crazy chain reaction that causes much of the structure to collapse. If you launch the bird at 74 degrees, it hits the block even harder, and the force whacks another block way out of place, but it does so in such a way that the structure remains standing, making it even harder to hit the pigs. Basically, it's the butterfly effect, the favorite metaphor of chaos theorists to describe phenomena like the weather where tiny changes in initial conditions make a big difference.
Since you can't precisely aim the birds, it's difficult to control the angle -- you just know that you sometimes get good results from hitting a particular area.
If you graphed the score you got from the full range of launch angles, it probably would have fairly chaotic properties in high-scoring regions. It would probably look like a one-dimensional version of this, which is a map of which magnet a pendulum ends up attracted to when started from different angles:

See those messy regions? Those are areas where your predictive power is diminished, where the score isn't up to you but instead up to something effectively outside your control. Psychologists have a name for this -- partial reinforcement. This basically means you only sometimes get rewarded for a behavior. The ironic thing is that this is more effective at entraining that behavior than full reinforcement.
There are other sports, such as bowling, that also exhibit these chaotic characteristics, but good bowlers have found a stable region in the chaos that they can hit consistently.
Angry Birds, once you reach a basic level of prowess, is less like a game of skill and much more like something else entirely -- a slot machine.
The funny thing about Angry Birds is that it's actually not a great game in one sense -- while playing the game takes some skill, skill is no guarantee of success.
The trouble is that your only control method, the angle at which the bird is launched from the slingshot, is the input to a chaotic system with sensitive dependence on initial conditions. If you launch the bird at an angle of 72 degrees, it hits a block off to one side and then stops. If you launch the bird at 73 degrees, it hits the same block off to the side a little bit harder, which starts a crazy chain reaction that causes much of the structure to collapse. If you launch the bird at 74 degrees, it hits the block even harder, and the force whacks another block way out of place, but it does so in such a way that the structure remains standing, making it even harder to hit the pigs. Basically, it's the butterfly effect, the favorite metaphor of chaos theorists to describe phenomena like the weather where tiny changes in initial conditions make a big difference.
Since you can't precisely aim the birds, it's difficult to control the angle -- you just know that you sometimes get good results from hitting a particular area.
If you graphed the score you got from the full range of launch angles, it probably would have fairly chaotic properties in high-scoring regions. It would probably look like a one-dimensional version of this, which is a map of which magnet a pendulum ends up attracted to when started from different angles:

See those messy regions? Those are areas where your predictive power is diminished, where the score isn't up to you but instead up to something effectively outside your control. Psychologists have a name for this -- partial reinforcement. This basically means you only sometimes get rewarded for a behavior. The ironic thing is that this is more effective at entraining that behavior than full reinforcement.
There are other sports, such as bowling, that also exhibit these chaotic characteristics, but good bowlers have found a stable region in the chaos that they can hit consistently.
Angry Birds, once you reach a basic level of prowess, is less like a game of skill and much more like something else entirely -- a slot machine.