If we use a digital camera to take pictures for a Web page, there’s a few things you’ll need to do with your images to prepare them for the Web. At the very least the photos will need to be rotated, cropped, cut out and resized.
Before I tell you how, I should really answer why. With most photographers capturing images in excess of 8-Megapixels you have way more pixels than you need for most ‘normal’ everyday uses. Uploading an 8-megapixel image to an online gallery or store is overkill.
The second reason you should crop an image is ensure that it is the correct shape (there is no use having an oblong image if the photo frame is square).
The third reason you should crop is to improve the composition (which is another way of saying that it is a good idea to get rid of all of the uninteresting or distracting parts of the image that you don’t want people to see). You can enhance or improve the image by just cutting, or cropping, the unwanted parts of the image off. This will make people think you are a much better photographer than you really are!