Raw Size: 400 X 300 Display Size: 400 X 300 Enlarged Size: 640 X 480	The raw or original size of this image is 400 X 300 pixels. When this image is enlarged, the browser will re-draw the image by multiplying the pixels resulting in some loss of quality.
Raw Size: 640 X 480 Display Size: 400 X 300 Enlarged Size: 640 X 480	This image is actually 640 X 480 Pixels. It is reduced for initial display to 400 X 300 pixels by using the width and height attributes of the image tag. (View the source of this page to see) When this image is enlarged, the browser will actually 'un-shrink' the photo resulting in an increase of quality.