To perform any action (such as moving, resizing, or deleting) on page elements, you must first select them.
Sometimes elements are automatically selected (for example, right after creation), but in other cases, manual selection is required.When a page element is selected, it will show eight grab handles — one at each corner and one at the middle of each side.
Covers the concept of a primary selected item, which has a special function when working with multiple selected elements (e.g., alignment or size references).