Glossary/Drawing basics
Handle
A unique, permanent identifier AutoCAD assigns to every object in a drawing.
Every entity in a drawing — a block reference, a line, a piece of text, a Plant3D asset — has a handle: a hexadecimal ID that's unique within that drawing and stays the same for the object's lifetime, even if it's moved, renamed or its layer changes.
Handles are what let a round-trip tool match an exported Excel row back to the exact object it came from after editing, rather than relying on row order or a value that might itself have changed.