Redo & Undo commands
Undo / Redo commands make it possible to undo and redo most actions performed in the editor.
Undo erases the last change made in the editor reverting it to the previous state. The opposite of undo is redo. It reverses the Undo command or advances the buffer to a more current state.
Both commands are activated by selecting the Redo / Undo options in the "Edit" menu or by choosing the relevant button in the editor's main panel.