If you have ever bowled with a house ball and saw other people bowling and curving their bowling ball it is in part due to the type of ball they are using. I would have to write a small book explaining it. But one step to improving your game is that you need to understand the game. That includes understanding the equipment. I have one video below showing and explaining it a little. But I found an article that, yes it is a little long, but is a very interesting and good read. After you read it, keep in mind that most house balls are plastic with no weight block. So when you see others like me bowling and striking with relative ease it is mainly due to the ball. Yes the accuracy is due to many hours of practice a week, but the improved pin action is created by the ball. You can improve your average by as much as 10+ pins just by getting one of those high tech balls.
Here is a link to the story........ http://en.wikipedia.org/wiki/Bowling_ball