The Distort command works like a combination of all of the above. You can stretch or shrink sides of the selected image, in any fashion you wish. The results can be rather odd, and experimentation with this command is suggested. This command allows a precise adjustment of the image size and resolution. You can adjust the size settings either independently, or with the proportions locked in a constant ratio.
Resolution is either pixels per inch or pixels per centimeter.
If you lock the file size, any adjustment to height or width, will change the value of the resolution proportionately. Throughout the process, you are updated to the amount of memory the file requires. If you find yourself running out of free space on your image's window, adjust the canvas size to give yourself more space. If you need to reduce the size of the canvas to match you image, it is probably best to use the Crop command or Crop tool, as it will automatically adjust the canvas size to match the cropped area. Manual adjustment of canvas size to match the image can be rather frustrating.