To create a smooth selection in Photoshop with one of the many selection tools, such as the Magic Wand tool, you must first select the Anti-aliased check box on the tool Options bar. This tells Photoshop to pick up a few neighboring pixels to create a gradational effect. The result is usually more appealing than the alternative hard-edged selection. Sometimes though, the stray pixels are radically different in color and this becomes really obvious after you move or paste the selection on top of lighter- or darker-colored pixels. When this happens, you may think the only solution is to manually delete the unwanted pixels with the Eraser tool. Luckily, Photoshop is intuitive enough to have the Matting commands, which are designed to remedy this exact sort of problem.