Webcam 1080p versus 720p Resolution
When a web camera is described as being HD 720p or HD 1080p it means that it delivers high-definition resolution. A 720p camera is an abbreviation for 1280x720 pixels of resolution, where 1280 represents the number of horizontal pixels and 720 represents the number of vertical pixels; therefore a 720p webcam will deliver a total of 921,600 pixels (or 0.9 MP or megapixels).
A 1080p camera, such as the Coralsix CW-201 model, is a much better camera, with 1920x1080 pixels of resolution, where 1920 represents the number of horizontal pixels and 1080 represents the number of vertical pixels, thus a total of 2,073,600 pixels (2.1 MP or megapixels). The “p” following the 1080 is short for “progressive scanning”. The quality of the video will be better when more pixels can be progressively scanned onscreen.
720p or 1080p resolution, have an aspect ratio of 16:9, which is a widescreen view. Cameras that have a normal aspect ratio (picture as tall as wide) will often be described by the number of megapixels.
Finally, VGA cameras with a 640x480 resolution are normally less expensive entry-level cameras, are not high definition and use earlier technology.