I was able to understand about resolution and size, open and edit an image in camera raw. adjust the tonal range of an image, crop image, paint over a color using a color replacement tool, adjust the saturation of isolated areas of an image using the sponge tool. Use of the clone stamp tool to eliminate unwanted part of an image. Use the spot healing brush tool to repair part of the image. Use the content-aware Patch tool to remove blemishes. Apply the Unsgharp Mask filter to finish retouching photos. saving an image file (JPEG) for use in a page layout application.