Flat panel displays (plasmas, LCD's etc) display their picture by turning on and off millions of pixels that make up the image on the screen. The more pixels you have, the better "definition" of the images you will have. Therefore, the higher the resolution, the better picture you will have. So if the salesman says "This TV is 1920X1080 resolution", that means the picture is 1920 pixels wide by 1080 pixels high. That is over 2 million pixels!

So what is 1080i compared to 1080p. Well, let's say that you took 1080 and divided it into even and odd numbers. In 1080i, the "i" stands for interlaced. That means it goes through all the odd numbered pixels and then goes back and fills in the even numbered ones. The sequence is interlaced.

1080p however is different. The "p" stands for progressive. Unlike interlacing, the progressive scan goes through all the pixels sequentially. This should provide for smooth movement in an active screen such as a sporting event, or stock ticker on MSNBC.