Verbatim: Vanishing Point tool Suppose you're trying to edit a picture that includes flat surfaces in perspective: receding gymnasium floorboards, say, or city buildings, or a moving van photographed from the back left corner. In each case, trying to paste or paint something into the shot is fiendishly difficult, because you have to maintain the same V-shaped shrinking away to the vanishing point. But if you click four corners with the Vanishing Point tool, Photoshop learns exactly how that surface recedes. Anything you paste or paint into that area shapes itself into perfect perspective. Copy a window from one side of the building, and Photoshop snaps it into the size and shape appropriate for the adjacent side. Suddenly it's easy to paint a new company logo onto that moving van or seamlessly repair a ripped-up section of those floorboards (by copying from an intact area). The new Smart Objects, unhelpfully named though they may be, are even more flexible. Ordinarily, anything you paint or paste into a Photoshop document becomes what is called a bitmap: a memorized array of colored dots, frozen until you paste or paint over them. But once you designate an area of your artwork as a Smart Object, the rules change. You can shrink that scrap of image at will, without worrying that you won't be able to scale it back up if you change your mind. (By contrast, ordinary bitmaps - Dumb Objects? - lose so much resolution when re-enlarged that they look jagged and horrible.) If you duplicate a Smart Object, furthermore, the copies are all linked to the original. Change one fire hydrant's color, and you change them all. Warp mode, which can distort a photo as if it were on a sheet of stretchy, curly latex. When you want to wrap a custom label around a soda can, or make a plasma TV ripple in the breeze like a flag, the Warp feature is just the ticket.

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Ockham's razor- It's that simple