Interlace and Progressive Scan

From Izzy Video Wiki

Progressive: The picture consists of full frames, in NTSC its 29,97p and PAL its 25p. p = progressive

Interlaced: The pictures consists of half frames, in NTSC its 60i and PAL its 50i. i = interlaces

If you monitor interlaced video on a LCD screen, scan lines in the picture might appear and that's because of the even and odd lines, and because the frame is divided into 2 half frames.