"She has been driving" = up until now "She had been driving" = up until some point in the past. For example: Lucia is tired at the moment, because she has been driving all day. Lucia was tired when I saw her yesterday, because she had been driving all day. The perfect tenses are 'bridge' tenses: The present perfect (have been) connects the past with the present. The past perfect (had been) connects a point in the past with a previous period.

She has been driving. Well, let's see why I'd use that construction. It's about the past and the present. Something started at some time in the past, and it might still be going on, or it might have just finished, and/or it has left some kind of evidence in the present. If she is tired you could explain that "she has just been driving." If her hair is messy you could explain that she has just been driving with the top down (in an open top car/a convertible). The past perfect refers to something in the past that is connected with another thing/action/event in the past. Like this - Because she had been driving all day she was too tired to come to my party last night. It helps to draw timelines and put the actions on the timeline. Do you know how to draw timelines? Some people draw time 'trees' ! Do you know how to draw time trees?

Thanks!

"she has been driving" = she is STILL driving "she had been driving" past action before another past action.. the actions are both now finished.