[quinny9]

Can anyone tell me what the difference is please?

[A n d r e w]

"i" is for "interlaced," where each frame is made up of two half-resolution "fields."

"p" is for "progressive," where each frame is made from one field rather than two interlaced ones.

Interlace - Wikipedia, the free encyclopedia
Progressive scan - Wikipedia, the free encyclopedia

With camcorders, the "p" is often used misleadingly. Many consumer level camcorders that offer a so-called "progressive" mode are really giving you interlaced footage in a manner which can be converted to true progressive by using sophisticated editing software.

Andrew.