It's easy and fast, and best of all, when you are preparing images or other items for the web, it works! Instead of cropping out the background of an image when you are getting ready to take that file to the web, simply use the Trim tool in Photoshop and let it do the work for you. Open up your image and select Image, then Trim. In the box that opens, simply select what you want trimmed and what you want the cropping based on and click OK. Then, sit back and watch Photoshop do its magic. Once it is done, Photoshop will have cropped your image with precision while you snacked on a few corn chips!