Why we use WPF ? what benifit it gives when we use it for web application and windows application ?

Question

Hi all ,

  Previously i was working with old win forms .net 2.0.Later
 
   I have used WPF for both my windows and web applications.Further
i have used WPF basic controls and NOT USED RICH OR ADVANCED WPF CONTROLS.

  But i dont know why i used wpf and what benefit i got ??

  I feel like only in front - end design part it is better to use wpf than old win forms.
  back-end coding there is only a very little different but concepts are same.i have studied in e-books that it improves hardware acceleration ,use 2d,3d graphics ..etc all those stuff other than what actually happens ?

  So can anyone tell me why we go for WPF ?, and
  What benefit i got in both web and windows application. ?
 
 thanks in advance