turning beachball

what and why do I get this turning beachball, is it bad connection somwhere or bad drive? It manely comes and goes when I am using the airport exteme.

It just means your computer is having trouble with some process or another. It's like the turning hourglass in Windows. It all depends on what you were doing when it appeared. I've never heard of it appearing in relation to wifi.

It could be that you have asked for some function to the Airport Extreme, and it is not fully connected. That can happen if you have just started the Mac or if it was sleeping and you just woke it up. As Oneironaut said, it's the equivalent of the hourglass in Windows. It indicates that the process you have invoked is in process and to wait.