The resolution of a surveillance camera’s image is measured in the number of pixels contained in the image. The higher the number of pixels, the more detail in the image. Higher resolution images give you the ability to zoom into the image to see fine detail.
VGA:640 x 480
D1:720 x 480
Full D1 (FD1), 960H: 960 x 480
1080p, 2.1 MegaPixel:1920×1080
(Images are for illustrative purposes only and are not actual camera images)
A 1080p image has more than 6 times the number of pixels as a VGA image.