Cropping recomposes an image by retaining a selected rectangle and directly reducing output pixels. It removes unwanted edges, switches horizontal or vertical framing, and fits fixed ratios required by avatars, article covers, and social platforms.
A crop does not move subjects inside the original; it discards everything outside the selection. A locked ratio keeps a series consistent, but people, text, safety margins, and visual balance still need inspection so important content is not cut unintentionally.