Explain any four facilities included in an interactive system that allows users to recoverfrom their mistakes

Undo Function: This is one of the most common features in interactive systems that allows users to reverse their last action. If a user makes a mistake, they can simply click on the 'undo' button to revert back to the previous state. This feature is commonly found in text editors, graphic design tools, and other software applications.

Confirmation Prompts: These are messages that pop up before the system carries out a potentially harmful action, asking the user to confirm if they really want to proceed. This gives users a chance to reconsider their action and prevent potential mistakes.

Error Messages: When a user makes a mistake, the system can display an error message explaining what went wrong. This helps users understand their mistakes and learn how to avoid them in the future. The error message should be clear and informative, guiding the user on how to correct the mistake.

Autosave and Recovery: Many interactive systems automatically save the user's work at regular intervals. If something goes wrong (like a system crash or power outage), the user can recover their work from the last autosave point. This feature can prevent loss of data due to unexpected issues.