[taw55]

I think he means that

A pixel is not a little square: http://alvyray.com/Memos/CG/Microsoft/6_pixel.pdf

[anmorgan]

Fair enough, his description seems misleading. To me a pixel is a discrete RGB value, which is made up of physical components, for example:

https://google.com/search?tbm=isch&q=close+up+of+lcd+screen

https://google.com/search?tbm=isch&q=stack+up+of+lcd+screen