[header] How to buy an hd monitor [title] Decide on an aspect ratio. [step] The aspect ratio of a monitor is the ratio between the width and the height. In the earlier years of the last decade, the 16:10 aspect ratio was the most popular among hd monitors, but more recently, the 16:9 " true widescreen " ratio has started taking over. 
In addition, the 16:9 ratio is the same ratio used by widescreen movies. Unless you specifically need a 16:10 monitor , 16:9 will be the more convenient choice.