Have you ever taken a great photo with your digital camera, it looks great on your computer screen but when your print it, it looks like a bad mosaic? This is most commonly due to a low resolution setting on your camera.
Most professional photo printers print between 150 and 300 pixels per inch or "ppi" to achieve photographic quality. If you wanted to enlarge a photo from your digital camera to an 8x10 print, that means you would have to take the photo at a minimum resolution of 150ppi or 1200 x 1500 pixels (8x150 + 10x150). The table to the left will give you an idea of the relationship between prints and resolution.
Therefore, it is adviseable to have your camera always set to the highest resolution for the most flexibility when it comes to printing your photos. One drawback to this is that the larger resolution means larger file sizes for your photos, decreasing the amount of photos you can keep on your camera at any one time.
You may also notice from the table above that the amount of megapixels your camera has limits the maximum quality and size you can ulimately achieve.
My photos look fine on my computer screen!
Don't be decieved by how your photos appear on your computer monitor, your monitor displays photos at 72 ppi, whereas photos are printed at more than twice that resolution.