Place the pineapple on its side on a cutting board. Using a sharp chef's knife, slice off the top and bottom. Be sure to make straight, even cuts so the pineapple will steadily stand upright.
Stand the pineapple upright and hold it steady with one hand. Using a sharp knife, cut the peel away from the fruit, letting the knife follow the natural curve of the fruit so not to cut away more flesh than necessary.
Next, remove the brown "eyes" or holes that remain on the flesh. There are several different ways to do this, but this is my preferred method: use your knife to trim away the sides of the pineapple to remove the eyes, making sure that you leave as much flesh as possible.
To cut pineapple wedges or cubes: stand the pineapple upright and cut the fruit away from the center core in planks. Discard the core. The core is woody and fibrous, so not pleasant to eat. Cut the planks into wedges or cubes. The pineapple is ready to use.
To cut pineapple rings: Cut the pineapple into slices about ¼-inch thick. Using a 1-inch or so round cutter, cut and remove the cores from the slices to make rings. The pineapple is ready to use.