And on a ZX Spectrum display, the horizontal lines were not contiguous in memory - you would get the 1st line, then the 9th, then the 17th.. then after you got

And on a ZX Spectrum display, the horizontal lines were not contiguous in memory - you would get the 1st line, then the 9th, then the 17th.. then after you got one third down the screen it would jump to the 2nd, then the 10th.. a right pain to program! Explains the weird loading screen effect, when the data would be loaded so slowly you could see it drawing in that odd pattern. Example: http://whatnotandgobbleaduke.blogspot.com/2011/07/zx-spectrum-screen-memory-layout.html http://whatnotandgobbleaduke.blogspot.com/2011/07/zx-spectru... And the icing on the cake being the colour information was stored sequentially at the end on an 8x8 pixel block basis!