I went to the local computer store to buy a replacement monitor for my home PC. My existing monitor is 19", that is to say the diagonal dimension is 19", and I am happy with this size. There were two types of 19" monitors in the store; 'widescreen' ones with a 16:9 aspect ratio, and 'normal' ones with a 4:3 ratio. The second type were not as wide, but they looked bigger. But which one was bigger? And how much bigger was it?