Do you even know what High Definition is? High Definition refers to the compression. A regular TV is only 320 by 480, this is why when you watch a DVD on your laptop or computer it doesn't look nearly as good as it does on the TV, because your laptop's resolution is a 1000 x w/e. Yes it's true Film is not video and it uses an entirely different process, however... the minute it's transfer to digital, it follows the same principles as video. The way it works, is there are 29 frames per second, that means 29 still pictures each second. Now think about how big a .JPG is, now think about how the size varies from how big the actual image is, now think well over 20,000 still pictures... That's going to BE HUGE! A DVD only hold 4 gigs, so it's compress to like 320 by 480. What HD means is that there's a larger storage capacity, HD being around 15 gigs, and Blu-Ray Between 25-50 gigs. Now combine this with the fact that HD-TVs put a resolution of either 720 or 1080, if you play a DVD obviously it's not going look good, your going need HD, which means video that has a resolution of either 720 or 1080(I don't know if they've decided on a ratio yet). This is why HD looks better because the IMAGE IS BIGGER!!!