> Now with LED and LCD displays they do More precisely: now there is somewhat a more common case where they do. Certainly in many contexts it is still helpful

> Now with LED and LCD displays they do More precisely: now there is somewhat a more common case where they do. Certainly in many contexts it is still helpful to think of pixels as points (images are very often transformed before display). But if you're talking about what gets pushed to the screen, it probably will be helpful to think of them as squares. Doing so lets you do cool tricks like sub-pixel antialiasing. And sure, you could still deal with subpixels in a "pixels are samples" model, but it would be a lot more awkward.