Undo Action:?

Short answer: The caretaker calls Save() to store a Memento whenever the text is changed. When an undo is triggered, the caretaker pops the most recent Memento from the stack and asks the TextEditor to restore itself to the state saved in that memento. Benefits of the Memento Pattern:

Real-world example (ShopNest)

Use a GoF pattern in ShopNest only when it removes duplication or makes a change safer—explain the problem it solves in the interview.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.