GDI+ hBitmap vs pBitmap vs pGraphics vs hdc

[smarq8]

What are difference between these 4 "things"?
Why most gdi function use other "things"?
I'm also confused when I should destory them. For example I convert pBitmap>hbitmap, so can I destory pBitmap? Or if I do not delete pBitmap and then make stuff on it, will this affect on hBitmap? And the similar thing with any other relations or direction. Or while I convert them then it "copy" or somehow "refer" to each other?

Thanks for any tips.