You can easily cancel the changes you make in a project. For example, if you accidentally place a data elements in the wrong drop targets in a visualization, and can easily reverse your changes.
You can reverse changes in two ways:
To reverse any edits that you made in a project since you last saved it, on the project toolbar click Canvas Settings and select Revert to Saved.
To reverse the last change you made to the project, on the project toolbar click Undo Last Edit. You can click Redo Last Edit to reapply the change that you undid.