difference between pifa and ifa antenna

Hi,
I don understand the difference between PIFA and IFA. Can u guys help me on this topic?

IFA : it is not planar
PIFA : it is planar , for instance , patch antenna !

http://www.poynting.co.za/tech_training/ifa.shtml

joelo,
i knew that. anyway thanx 4 the website. is the shorting pin gives impact to the antenna bandwidth?
how do we enlarge the bandwidth?