Image Resolution

Image resolution is a tricky subject because the explanation can be somewhat technical. Basically, resolution is a measurement of the width and the height of the image.  The unit of measure is a pixel.  Images with higher resolution have higher pixel counts - meaning the product of the width and the height is greater.  When printing with digital images, higher resolution typically means better results.

If you don't understand this explanation, that's alright. All you really need to know is whether or not the images that you upload will print well at different sizes. In the photo gallery view, you will see a colored bar graph next to each image. This represents print quality for various output sizes. The legend to the left indicates the meaning of each color.

4x6 5x7 8x10 wallet 11x14	This examples shows that the image is recommended for wallet and 4x6 prints but not for 8x10 prints. 5x7 prints may look acceptable but the quality may suffer.
If you choose print images in non-recommended sizes, the resulting image may look pixilated. This is just a fancy word for the below effect:

Clear image on screen

Pixilated image when printed