Unless you frame every shot perfectly (can anyone outside of a studio?) you will inevitably want to “reframe” some of your photos where your subject is not quite where you want them, or maybe to take out distracting objects close to the edges. If these adjustments can be made by retaining a rectangular section of your photo, and disregarding the rest, then that is exactly when cropping comes into play.
Here is a guide to cropping your photos using Photoshop Elements, which can be equally applied in actual Photoshop.
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