Paging comes into picture when you are interacting with large database. Advantages are :

1)You can process the data in Batch size which gives less load to the system at a perticular time.

2)If your system breaks at any point of time and u r resuming the same in the next round, you can continue for the rest.

3)your datasize per request is reduced. Which in turn improves the network as well as application performance.

I hope, this may help you.

Umesh