The image below demonstrates the Random Points within a Square to Calculate Pi concept:
Image:gpu-pic1.jpg |thumb|widthpx| ]]
The number of tasks are equals with the number of thrown dart. Every task executed on the GPU, and performs the calculation which verifies if the point is inside of the circle or not. This tasks are able to execute the work independently, because it does not requires any information’s from the other task. Finally the host gather all the synchronize data from the device, and calculates the size of the PI.