Remove Unused Elements

After working in a drawing for sometime, some elements might be created but not used at all
You might created extra layers, blocks, annotation styles, and no longer used
Each of these unused named objects can significantly increase the file size
Remove all unused named objects will help to reduce file size

Application menu > Drawing Utilities > Purge

Named Objects: View items you can purge

Purge: Remove selected unused named objects only
Purge All: Remove all unused named objects