Xara LX allows you to Undo your most recent changes to a document. Undo allows you to get rid of changes which you've applied mistakenly to your document, which went wrong or which you simply don't like the look of. Undo is a very powerful tool when combined with Redo because it gives you the freedom to experiment with a drawing, secure in the knowledge that you can always undo any changes or if you eventually decide you do actually like the changes, to redo them again.